These People Found Utterly Devious Loopholes
Ever get surprised getting a little more than your money’s worth? Ever do it again? Whether it be mislabeled products, badly thought-out promotions, or broken vending machines, these 50 Redditors found devious little loopholes that kept them coming back for more.
1. A Free Tank Of Gas
My husband used to work for a local grocery store chain that has gas stations. About ten years ago they came up with a promotion: You could buy groceries, then after a certain amount spent, you earned a few cents off your gas per gallon. Something like every hundred dollars gave five cents off per gallon. It was pretty nice.
Except when it first came out, they made one huge mistake. They didn’t think to limit it. Families would share the same points card and build up points until there was more off per gallon than it cost, making it free. Then they’d get together, enter the points at the station, line up their cars, and everyone gets a free full tank of gas. Technically totally legal.
Not long after, they put a cap on how much off could be earned and that you could only use one car per transaction. But for those people who pulled it off, kudos.
2. Chicken Or Beef?
Once at the grocery store, I noticed that the typically eight-dollar stew beef was mislabeled as three-dollar chicken breasts. I inconspicuously slid six-packs into my cart and slunk to the self-checkout to see if the label would read the mistaken prices. “It’s going to be the usual eight dollars,” I think to myself, “I’m not that lucky.”
But that day, I was that lucky: each pack was about three dollars. I bagged my stash and made my getaway to the car when I started to think, “Why stop now? Why not have stew beef for days??” I stashed my loot in the car and went back inside for another round of beef. Was that just a small fluke I had found before? Nope, it was not.
Someone royally screwed up, because ALL the stew beef was underpriced as cheaper chicken breasts. Ordinarily, I’m modest in my shopping, but this was enough to let my inner greed take over and I decided to just take everything. I was picking out another pack of six when I nearly had a heart attack. One of the workers noticed me raking meat like crisp autumn leaves in a forest.
He starts to walk over. “Oh no, the house is on to me,” I think. GO FOR BROKE. In my greed, I grabbed three more packs to dump into my cart. I ended up having to leave the last remaining two behind, and passed the clerk with a brisk “Hello” as I make my exit while he inspected the gaping hole I had left in the meat section.
I’m guessing that he found their mistake and put two-and-two together, because I’m about halfway down the cereal aisle when I hear a loud, exasperated “Oh, COME ON!” I wasn’t even being sly anymore. I hurried to the self-checkout, cashed in my winnings, and hustled out of there trying to think of how many different recipes to make with my 15 packs of $45 stew beef.
3. Printing Money
This was the greatest thing that ever happened to me. About 12 or so years ago a certain popular bank chain started rolling out ATMs in some locations which dispensed $10 bills and not just $20s. For about three days there was one ATM in my town which only dispensed $20s but had the new firmware and gave the option to dispense in denominations of ten dollars. So, if you ask for $100 in tens, the machine would spit out ten bills – only those bills were $20s.
So, you get $200. I did this three days in a row. I only stopped because they fixed it.
4. Money-Making Soda
There was this K-mart promotion where if you bought a pack of batteries and three cases of soda, you’d get a $20 gift card. The thing is, the batteries and soda cost $19.12. My friend, roommate, and I went to every K-mart in Las Vegas, each separately, and kept reusing our gift cards to redo it. By the end of the day, we had enough soda for at least a year and a kitchen drawer full of batteries.
5. Stretching My Meal Plan
My college had a dining hall with continuous hours from about 7:30 AM to 9 PM. The meal plan I could afford only gave one and a half meals per day with a decent bit of flex money for the various campus vendors. I discovered fairly early on in the school year that I could enter during the latter half of a meal’s service and park myself around the midpoint of the seating area with my laptop and a textbook.
If I stayed quiet, I could typically work one single meal ticket for two full meals plus plenty of beverages. Pretty sure a few of the cafeteria ladies knew what I was up to, but because I kept my space clean and didn’t cause any fuss, they never told me to leave despite it being against the rules. They probably assumed I was studying, which was accurate maybe half the time.
6. Rolling For Burgers
There is an app for a local burger chain where it allows you to “roll the dice” to get a code for a free double-patty burger upgrade. It was designed so you could only try it once per day and it even shows the date of the roll on the code so the cashier could verify it. However, I found out that you can just change the date on your phone and try again immediately.
If you got nothing, change it again and just keep going until you get the code. Then when you get the code, you change the date back to current date and the app will update the code so it looks like you rolled it today. I got free burger upgrades for years until they finally got rid of the feature altogether. I don’t know if anyone ever figured out this exploit, because they removed the feature for other reasons.
7. Just A Few More Pages!
In one university class, they made us print out these 20-page state diagrams when we could have just as easily handed it in by sending them a file. Well, I got my revenge. See, the university printer system was very easy to take advantage of. You could send two documents to the printer: The first one would be a single page, and the second one would be the long document you actually want to print. When you go to the printer, you’d select the first document and delete it.
The second document then moves up and gets selected, but the price doesn’t get updated. Because of this, you could print out as many pages as you want for the price of a single page. It was their own fault really. This was a long time ago, and the bug was fixed, but only shortly before I graduated.
8. Gold Dispenser
I found a vending machine at work that didn’t differentiate between quarters and golden dollar coins when dispensing change; when it was supposed to give you quarters about half of them were golden dollars. I put in as many five-dollar bills as possible and bought the cheapest item available and got about eight dollars worth of change back each time. My total profit off that machine was over $50 before it ran out of golden dollars.
9. Extended Parking
In Seattle, I have to pay for street parking every day, and there are two ways you can pay for it: pay at a meter and put the ticket in your car, or use a phone app. The street I park on only allows four hours at a time, so when I get there in the morning I’ll pay at the meter and then use the phone app to pay again four hours later while I’m at my desk.
10. Please Hold…
At the old call center I worked at, they made it very clear that calls less than two minutes, and greater than 15, would never get listened to by Quality Assurance. That rule was accurate the entire time I worked there. So, I used the rule to put the rude callers in their place. When I had a jerk we didn’t want to deal with, I could just put that caller on hold for 5-10 minutes for no reason as I “looked into that” for them…and then hung up the call with no possible repercussions.
11. Turning The Lights On
At my job, we sold LED lights and for a couple of months, the electric company was doing a rebate on them. They were ten dollars for a two-pack of lights, but with the rebate, it was a dollar. The limit was five boxes of lights per transaction. So customers were getting $50 dollars’ worth of lights for their house for five dollars. I got a ten percent commission on anything I sold, and since the electric company was still paying for the bulbs, I was getting a commission on it.
Everyone walked out of there with ten light bulbs. I would help around 100 people a day. I was selling $5,000 dollars’ worth of LED light bulbs a day on top of all the other stuff they would buy. I would give ten percent off your entire bill if you for some reason they didn’t take them because even if you spent $200 and saved $20 I was still making an extra $30 off you. My company also had a sales competition to see could sell the most lights. I made so much money those months.
12. It’s All Expired!
Kroger, the grocery store chain, used to have a policy that if you found an item on the sales floor that was expired, they would give you an equivalent item for free. So, in college, me, my roommate, and my girlfriend would go to Kroger at midnight and go through the meat, dairy, and bread sections looking for things that had just expired due to the change in date.
I had discovered that they didn’t go around pulling newly expired items until around 5:00 AM, so we would consistently roll up to the register with a cart full of chicken, steak, bread, and cheeses, all for free. They hated us, but it was their rule.
13. Blind Carbon Copy
There I am, a freshman in community college going into Radio Broadcasting. It was exceedingly difficult to get a parking spot because my classes don’t start until 9 AM and everyone else is already taking 8 AM classes. The parking situation consisted of a large lot out back, but not nearly large enough for the student body and staff.
There was a lot to the side and a lot across the street you had to pay to use because it was privately owned. Each one involved a 5-minute walk just to get to the building, not to mention navigating through it to get to wherever your class was. So one day, I’m running late and, in my haste, just park in a small visitor lot right in front of the building.
The place is like five parking spaces wide and a 45-second walk from my car to the classroom. At the end of my day, I go back outside and find a ticket on my car. It’s hard to read because it’s a carbon copy of the ticket they wrote. So hard to read, in fact, that I could not even make out the date and time it was written.
And then it dawned on me. Why not just park here every day, and put this under my wipers before I go in? It wasn’t foolproof by any means, but worst-case scenario I get another fine and maybe an angry letter. I spent three years there, taking classes or working at the campus radio station, and I NEVER once got called out for it. I even had the presence of mind to put the ticket in a little Ziploc bag if it was raining like they did.
14. Clocking In And Out
When I was clocking in at my previous job, it was rounded to the nearest 15 minutes. I decided to clock in on the sevens and out on the eights. For instance, I would clock in at 8:07, and clock out at 4:53 or 5:08. Because of the rounding, I was able to save essentially two and a half hours of work every single week.
15. Extra Value Meal
This one was satisfying—but also embarrassing. One day, long ago, when times were new and things were different, I was waiting in line to order at McDonald’s. The guy ahead of me ordered a six-piece nugget. I thought to myself, don’t get a six-piece nugget, get two four-piece nuggets. He turned around and said, “What did you just say to me?” And I replied, “Oh god, I said that out loud, didn’t I?”
I explained to him that, at the time, six nuggets were two dollars and sixteen cents. The four-piece nuggets were on the one-dollar menu. He could have been getting two more nuggets for sixteen cents less. He turned back to the counter and told the guy there, “Yeah. Do what that guy said.”
16. Gaming The Shopping Cart
Target had a deal on their website where if you put an in your cart and then added things like a controller or other accessories, you would get percentages off your total. The thing is, if you removed the extra accessories from the cart as you were checking out, it wouldn’t take the discount off. I got a $400 Xbox One about four years ago for like 150 bucks, and gave it to my dad as a Netflix machine.
17. Running With The Doc
I have some health issues but I’m also a runner. I run a few races every year. My neurologist knows this and thinks it’s fantastic, so he will write me orders for all kinds of stuff; compression wear, different support braces, and shoes because I can get them from the med supply place with a script, and my insurance will buy them. I wasn’t even aware that I could do this. I see him every three months and every time he calls in new stuff for me.
My insurance doesn’t put a cap on how often I can get new ones. I get these insane custom cast shoes that knock anything else I could buy out of the water.
18. Free To Win
A while ago, I played a pay-to-win mobile game called Blitz Brigade. I figured out you get about 6,000 in premium currency if you hit a certain button in settings. I gave myself more than one million of their premium currency, which you’d normally have to pay a lot for, and proceeded to be invincible and extremely deadly for about a week. After that, I was permanently banned.
19. Yup, I’m On The Floor
Years ago, I was a season ticket holder for an awful NBA team. My tickets came electronically via PDF. I had okay seats in the upper part of the lower bowl, but nothing great. Most nights I knew it would be empty unless a superstar like Kobe or LeBron was in town. On those days, I would deploy my ingenious plan. I would use the full version of Adobe Acrobat to edit the PDFs to indicate a much better seat location than mine.
The bar code still scanned just fine because I didn’t mess with it, but when the usher took my printout all he saw was that I was sitting on the floor. Got away with it for years until the team actually got good for a while and the place was packed every game.
20. Everyone Uses This Phone Number?
I went to a sporting goods store, and they asked me for my phone number when I was paying. I was in a bad mood and didn’t want to fight with the clerk, so I told them our local area code and 555-1212, which is the old number for directory assistance. The clerk accepted it and I left. When I checked my receipt I had a huge number of loyalty points—because apparently, a ton of other people did the same thing.
I knew exactly what to do. I called the office the next day and switched the “account” to my new address. A half-dozen times over the next few years, I went and got free stuff with all the points that I kept racking up as one of their most loyal customers.
21. A Whole Bag Of Snacks
I once went to a vending machine, put a dollar in, bought some chips, and it gave me my money back. I tried it again, and the machine gave me four quarters back again. With one dollar, I bought the whole row of chips. I ended up having 40 bags of chips and a bunch of gobstoppers and crackers. When I went down the next row it kept my money, and thus the glitch ended. I completely filled my bookbag though, so I probably wouldn’t have been able to carry more.
22. Double Doctor Pepper
In Virginia, Dr. Pepper is distributed by Pepsi. In Tennessee, is distributed by Coke. Our store district overlapped both states. One time they applied for both the sale of Pepsi products and Coke products. Five six-packs of 20 oz bottles of Dr Pepper ended up selling for 99 cents each. I bought so much Dr. Pepper and told everyone I could about that deal. Funny thing, they did the same promotion again about a month later.
23. Through The Firewall
At one of the hospitals I work at, the Wi-Fi is so locked down with firewalls, it’s almost useless. You can’t log onto ESPN, much less any gaming sites or even the Apple App Store. When I’m working in the middle of the night and it gets slow, I like to play games. I learned that I can use my phone as a hotspot until I get logged in.
After, I could switch my computer over to the hospital WiFi, and I somehow could get through their firewall. This also worked with downloading large files and updates from Steam.
24. Canceling Cancellation Policies
I travel a lot, but because of that, I usually risk tons of money canceling hotel reservations at the last second. Instead of accepting the penalty for canceling at the last minute, I move my reservation to three days later…Then, I call back after some time has passed so I can fully cancel my reservation at no charge.
25. Very Long Weekends
I once worked at a call center that would let you call out two days in a row as long as it was for the same reason and only counted it as one absence. Their thinking was most people could use two days when they call out sick but are afraid to take it and that makes more people ill. What most people did was realize they could call out between their split days off and give themselves a four-day weekend.
They asked a girl once why she always took two days off and she was like, “You give me the option and you’re surprised when I take it?”
26. The Overachiever
While I was at university, I figured out I could weasel in an extra degree by overloading more than once a semester. Typically, you took five credits each semester, and if you were in good standing, you could take an extra one. You’d make it a total of six classes, or 12 credits per year. I figured, by trial and error, that I could overload more than that.
For example, the Dean of Science gave me permission to overload. I could then go to the Dean of Socials to overload again. The computers never picked it up. So for three years, I overloaded, collecting up to 9 credits each semester. By the time I finished my fourth year, I had a stand-alone BA. I got that on top of another HBA and BSc. Then, they figured out my plan.
The university tried to demand I pay, but nothing in the course calendar or rules said what I had done was wrong. They changed it the rules the following year.
27. Grounded No More
When I was in school, they sent us home with a form for our parents to fill in. The idea was to collect updated contact information in case anything had changed, like phone numbers. If you were late to school, the school texted your parents to let them know. I saw my opportunity—and I took it. I was frequently late, so I filled the form with my own phone number and started to receive the text messages that were intended to tell my parents that I was late.
I got grounded far less frequently after that.
28. Canned Food Drive
On my grocery club, the promo for the week was one thousand points for canned veggies. A can was just under a dollar, so if I buy a can, I get one thousand points, which equals a dollar in rewards to spend another time. I loaded my cart, and got paid $112 dollars of points on my card. But I didn’t stop there. Then, I took it to the food bank. They were really happy for the canned food.
29. Always Grieving
At the company where my mother works, in the human resources department, her assistant found a loophole that the overtime reports didn’t flag bereavement hours, no matter the hours…She stole half a million dollars over three years as a part-time employee making $18 an hour. She finally got caught by my mom, because of a random comment she made that raised an eyebrow.
30. All You Can Eat, All Day
Back when I was homeless, I found this newly opened place that was a 24-hour all-you-can-eat buffet. Yeah, I guess they didn’t think that through. I went there, paid the $9.95, and just spent the entire winter in a warm restaurant, on a soft sofa bench, eating and drinking very slowly and occasionally going to the bathroom. It totally beat sleeping outside in the snow.
31. Automatic Mark Machines
I’m an IT major at a community college. We use Cengage’s Mindtap for pretty much all of our coursework. And the way one professor who teaches the majority of the classes does it means you don’t have to do any work. The labs are just instructions on how to do something, followed by questions. You can just show the answers to the questions and not lose anything from it.
The lab simulations are having to do a series of tasks in a virtual machine that they run. He just checks to see if you marked them as done, so you can start it, leave it running, mark it as done, and get full credit. I try not to do it too often since this is my major, but sometimes you just don’t have time to deal with it, especially with how poorly the virtual machines run. Plus, he has assignments that you actually have to do, and tests, so I don’t feel too guilty about it.
32. Coffee Trade-In
So a few years ago had a program where if you bought a pound of ground coffee and then brought the bag in they would give you a free small coffee. Well as it turns out, the program ended two years ago, but up until a month ago, the staff would just do it for me because I asked. I didn’t know that they had stopped that program until they got some new staff and I looked it up, but hey, I had a good run there.
33. Unused Textbook
I just took a Calculus course over the summer and the online textbook was required for homework. They give us a two-week free trial for leniency. I noticed there wasn’t a date for the trial’s ending period, so I just never bought the book because the class was pretty easy for me. I saved myself $350 as I didn’t need the physical book or the online homework access code.
34. Shopping Around For Money
I used to get free money directly from the bank! I live near the border of Canada in the US. Because of that, the local banks often have a lot of Canadian money that people going to Canada can exchange for and vice versa. However, because of the changing markets and time of exchange, the banks have a different value of that money.
So, for example, one bank has $900 of Canadian cash that you can exchange for $1,000 USD, and the bank down the road will give you $1075 USD for that same $900 Canadian. $3,000 and two miles of driving between banks, and you make $225. This only worked because I was using local community banks with one or two branches.
The community banks can actually set their own prices for money. So, we had one local bank that would not give you much at all for your Canadian money. They just didn’t want it. For some odd reason, people wouldn’t shop around and just take what their own bank would give them.
35. I Don’t Believe In Homework!
I did not do this, but I remembered back when I was in college there was a statement on all the syllabus that no student would be required to complete any assignment that violated their beliefs. No professor ever elaborated on that policy, and I never saw any student pull that card, but now that I’ve long graduated, a morbid curiosity enters my mind.
What would happen if a student were a lazybones and pulled the “all assignments violate my beliefs?” Could they get away with doing nothing and still pass and graduate?
36. Another New Customer?
Even though I hate shopping at Walmart, they have this grocery pick-up where you order your groceries online, drive to the store at your appointment time, and they put the groceries in your car for you. The loophole is that for new customers, if you use a coupon code, you get ten dollars off. Every single time I use this service, I create a new email address so that I can use that coupon code.
37. Ziplocked In Deal
There was a deal where if you buy two boxes of Ziploc bags, you get a free movie ticket. The cost of the two boxes was three dollars less than a ticket and the coupons for the movie didn’t expire for a year. Anyway, I bought something like $250 worth of bags, and had free movies every week for a couple of months. I literally bought all the boxes off the shelf in two stores. It took me over a year to use all the bags.
38. Using The Answer Key
I took French 202 my sophomore year of college. My professor made us take these quizzes on a website where you had to buy the book and enter a code to access the quiz. Early on, I figured out its fatal flaw. If you got questions wrong, it would show you the correct answers and let you retake the quiz. I did usually try the first time, but I always ended up using the answers the website gave me.
39. The Survey Master
This website had a sponsored advertisement claiming to give a $5 Amazon credit if you do a survey. 25 minutes later I got an email with the $5 gift card. First, I got around the one survey per person issue. I got it down to under 10 minutes, but then they put a time minimum because it was red flagged. Okay, now it’s a challenge. I then started doing multiple surveys at a time, using my desktop and laptop, and using multiple browsers.
I was doing around eight at a time over an hour. After about a week, I guess they got enough results, which I probably horribly skewed, and thus it came to an end. All in all, I got more than $350 in Amazon credits.
40. The Biggest World Power
In geography class once, we were playing a little game where you were assigned a country with a few resources which grew in value based on the number of them you held. I realized the rules doubled agricultural resources every payoff but only really added 20% value to industrial ones. Even though that 20% of value is higher than five agricultural resources, a doubling of your value is a doubling.
I decided to trade all my industrial resources for other people’s agricultural ones. My class thought I was nuts because I lost most of my value that turn but in the end the teacher ended the game early because my wealth doubled every turn and everyone else had a far worse return. Since we were playing as countries and I had started as Ecuador, the game was ended because I was a turn away from becoming the biggest economy in the game.
I would have beaten the US, and completely ruined the point the game was trying to make in that starting wealth leads to ending wealth. Screw that, I made Ecuador the world’s biggest economic powerhouse.
41. Pizzas For The Coach
A number of years ago, I was a teacher and coach at a local high school. We held a fundraiser for our football team, and when it was over, I got around 25 leftover coupon books that weren’t taken. Each coupon book had a coupon for one free medium pizza, no purchase necessary. In the next six months, I ate 25 whole free medium pizzas.
42. Unlimited Data
Optus, an Aussie phone service provider, used to have a prepaid unlimited credit cap for three dollars a day. So I signed up for the cap, put the sim card in a spare phone, and used it as a Wi-Fi hotspot, making occasional phone calls and SMSs to my regular mobile just to make it look like I was using it for a phone. I was essentially getting unlimited data for $90 a month. At my peak, I was downloading 20gb a day. I kept it going for three years before Optus clued into what I was doing.
43. Gaming For Points
When GameStop was maybe a year or two into introducing paid pro membership, my best friend and I exploited how their points were earned in a ludicrous way. We purchased a used game for the highest we could. I think it was $57.99, some triple-A title. Since it’s used, we had seven days to return it. Well as a pro member, you used to get double the points at the time for purchases and trade-ins.
After six days, we returned the game and purchased another, all the while keeping credit if we wanted a game that was less than a triple-A title. Well after a year of doing this, our pro account had well over 100,000 points. We used those points to get coupons for stuff like “$50 off any product” and such. The good ones, you know?
This doesn’t work anymore. If your return games now, the points go back.
44. A Bounce From The Past
A million years ago when I was still all up on the Neopets train, I discovered that on a terrible computer, if you opened a bunch of tabs, it would make the flash games run really slowly. Not a benefit for most games, except…Hasee Bounce. With that game slowed and buggy, more doughnut fruit would be on the screen at once, which meant more combo multipliers, which meant higher points.
I used to live in a very rural area with really slow internet. Anyway, I’d rent movies on Amazon and stream them, but the definition would get pretty rough sometimes and it’d have to buffer a bit. I learned Amazon will refund you if you rented a movie and it gets a notice that the streaming wasn’t great. I rented a whole bunch of movies I normally would never pay to rent and got refunded for all of them.
Yeah, I was sacrificing quality, but I basically had a “free” streaming service until I moved and got better internet.
46. Don’t Cut The Cable!
I got free cable TV for the year I lived in my first apartment. I wasn’t planning on getting cable, but noticed it was working. It wasn’t included in the rent and at first, I thought the previous tenant paid through the month and the cable would eventually turn off. But it never did. Don’t know how or why it happened but I didn’t complain!
47. The Frequent Flier
I had a buddy that worked for American Express when the new dollar coins came out. He immediately came up with an incredible plan. He was able to secure a $40,000 line of credit because he worked there. He would buy 40k in coins for the points, open them all, take them to the bank and tell them he was a coin dealer looking for misprints and they would deposit 40k into his account.
He’d rinse and repeat over and over again. He ended up with four million airline miles on his card. He once took a trip overseas, and instead of finding a hotel, he would fly somewhere first class that was an eight-hour or longer flight so he could sleep on the flight. He was also able to buy tickets for people at $0.03 a mile.
48. The Art Of Misdirection
You remember those cards at McDonald’s that you put the stickers from the coffee on, and you get a free drink every seven drinks? Well, my father would fill out the card with the stickers, go through the drive-thru, tell them that he had the card for the free coffee, order something else, then talk to them a little bit. It was all a part of his plan.
He would pay for the food he ordered, the drive-through person would say bye, and he’d drive away. They never asked for the card. And if they did, he’d give it to them, simple as that. He’d take the sticker from his free drink and put it on another card. I remember he had a stash of about a dozen of those cards, completely filled out.
He did this every morning and would eventually meet everyone that worked there and would have casual conversations with them to distract them from the free drink even further. Being the teen in the passenger seat, I would have conversations with everyone, and they would ask me questions about school. It really just goes to show how far you can get with a little distraction.
49. There’s Free Wi-Fi!
There was this airline that I flew once that had inflight Wi-Fi, but you had to pay a ton to use it. However, if you chose to use their entertainment system, you wouldn’t have to pay. Well, I wasn’t about to let them rip me off. The thing is, you had to download their app to use their entertainment system, and to download their app you have to go to the App Store, so they let you use Wi-Fi to download the app and redirect you to their page in the App Store.
I just left the App Store and continued to browse whatever I wanted with the connection they provided me to download the app, but instead, I did whatever I wanted. Free full-speed inflight internet was so great. The last time I flew with them though this didn’t work, so I guess they corrected this bug. Oh well, it was good while it lasted.
50. Snack Strike!
In my high school, you could take a bowling class instead of regular gym class and it involved the class taking a bus to an actual bowling alley to play, which was a thousand times better than gym, so everyone wanted to take that class. Well, at the alley, there was a glitched-out vending machine. If you put a $5 bill in and punched in the number, it would give you your snack and also spit the $5 bill back out.
You could do this as many times as you wanted and never spend any money. After a couple of times doing this every class, me and my friend started to tally up how much we would have spent. Throughout the duration of the course, we ended up with over $150 worth of snacks without spending a single dollar. They ended up getting a new vending machine, but by that time we were already done with the class.