I went to a Gameworks once and went to a game that was something like a spinner on a dial where you just had to time a press of a button to get it to stop at a place that gives you tickets. My friends and I figured out that if you get it on a winning place once, then spam the button, it'll start and stop almost in the same place. Which is a pretty simple loophole. But we were like, 12 and the attendant behind the desk watched the whole thing and made us stop after we nearly ran it out of tickets. I remember him being mad at us and I remember that making me mad. Not our fault your machine can be cheesed by 12 year olds.
When my son was about 7 years old, we were at Chuck E. Cheese and he found a game where the tickets kept spitting out without paying to play the game. Needless to say, he had a ton of tickets to turn in and chose the dusty lava lamp on the top shelf. Ended up keeping it for years
I moved 2000 miles to a new city before my senior year of high school. Got lost at the school on the first full day and ended up in the teachers lunch room - it was basically on the other side of the kitchen from the students lunch room.
Anyways, no one said anything so I decided I'd push my luck and use the teachers lunch room until someone said something. I decided it would be best if I was extra nice to the lunch ladies also.
No one ever said anything about it. I never stood in the student food line. I felt like a bit of a dick about it sometimes, but come on. That's a golden opportunity.
Pub near me did a pint of IPA for £2.40 or a half pint for £1, so rather than buy a pint for £2.40 I'd buy two half pints for £2. Did this for months before the owner caught on.
7-11 had a promo when you used the ATM, there was a coupon printed on the back of your receipt for a free hot dog. My roommates and I would go in and do balance inquiries for free hotdogs.
Back in the day you could redeem Apple gift cards on iTunes and spam the redeem button and it would redeem the card half a dozen times or more times. If you ran a clicker script you could get more.. but let's just say I'm glad I never gave them my real name, address, or credit card info when creating my account.
When I was in high school Sprite (or 7-up?) Had a contest going where something like 1 in 7 caps would give you a free soda. Thing about these drinks is that they're clear. Not clear enough to flip over and actually read the text, but clear enough that you could see whether they had one line of text or multiple lines. So while the non-winners just said "Non-winner", the winning caps said something like "Congratulations! You won a free Sprite!" It was like 4 lines. Very easy to see through the bottom of the bottle.
My friends and I drank free soda all summer, although we did get accused of opening all the bottles to find the winners when we got cocky and like 5 of us went through the line together, redeemed one cap then unscrewed the cap and handed it to the guy behind for him to redeem all down the line. We had to explain the flaw to the store manager to get him to let us go.
Chick fil a had a deal where you'd get a free chicken sandwich if you create an account in their app. Well, they didn't require email verification so I ate about 50 free sandwiches last september.
I didn't "abuse the hell out of it" but it was common abuse where I worked.
If you clocked in late it was 1/4 of a call in. If you forgot to clock in, it was 1/8 of a call in.
So if you showed up late, it was better to "forget" and submit a manual time card saying you were on time.
The Moe's Free Burrito scam. I'm not sure if all Moe's Southwest Grill locations offer the same promotions but the one by my house when I was in college had a promotion that my friends and I abused pretty hard. We went in one monday, Moe's Mondays was like a ritual to us, and we pay full price for our burrito, chips, and drink. On the receipt there was an offer that if we go online and take their survey we will receive a coupon for a free burrito. Now the catch is, if you just go in and get a burrito and nothing else, well yea you won't spend any money and that's great right?! Well my friends and I realized that by redeeming the coupon but also paying about $1.30 for a drink you could get another coupon, and take another survey, and get another burrito. I think you can see where this is going. When I say we abused this hard I mean we would eat Moe's just about every day for almost an entire semester. Eventually the Moe's closest to us began recognizing us pretty quickly so we had to start driving around to other locations to get our dirt cheap burritos but damnit if it wasn't always worth it.
Cinemark used to have frequent flyer mile stickers on the drink cups in movie theaters. I'd go in after a movie and peel them all off. Redeemed enough for a free trip to Europe.
Subway 6 inch sub stamps - usually I could walk around the parking lot and in 5 minutes find enough stamps to fill a card, and get a free sub.
I actually only did this once - and you may still be able to do it. But Apple has an academic discount where you have to send them a photocopy if your school ID. As I understand it, they check with the school, so no chance of forging fake college ID. I had been out of college for at least 10 years, and wanted to buy a Mac Pro. So... I enrolled in a local community college, signed up for one class - which cost me a whopping $30. Used my new college ID to save several hundred on my Mac Pro.
Edit - this was in Pasadena, CA probably about 2006. I don't remember exactly what I saved, but it was somewhere around $300. Also, I made the purchase online, hence sending Apple the photo copy of the ID.
Worked for a Midwest coffee chain (way longer than I should have). At one point the company brought in a new POS system that was truly a POS (pun totally intended, the company that sold it to us went bankrupt and also sold the software to said coffee chain).
One of my fellow employee found out that instead of ordering a usual food item and get the 30% employee discount, you could order toast and add any item as a topping for no additional charge, while still getting the 30% discount. Came out to $0.85. Named it the "toast hack"
You could have any sandwich you wanted, completely customisable. Smoked salmon, avocado sandwiches on multigain bread? 85 cents. Blts with extra extra bacon? 85 cents.
Lasted almost a year before corporate caught on.
I've written about it a couple times, but the billing system Comcast uses has a loophole that allows you to reset a customer into promo pricing. By downgrading customers to just internet then refreshing the page i could save them $50 - 100 on thier bill. Not only that but i earned a commission on all the "new" video and phone sign ups. Commission for phone in particular was about $35 a pop. I set up over 50 new phone lines one month.