No matter how airtight a contract, rulebook or written policy may be, there will always be a loophole.

Rich people doing their taxes. Down-bad dudebros using AI errors to create raunchy content of Taylor Swift. Heck, there’s a reason why the contract between Marvel and Sony is (allegedly) kept under lock and key — neither company wants the other poking around in their highly-complex legalese.

But it isn’t just weirdos and celebrities that are privy to discovering cheats in the system. From using geographic errors to get free Buffalo Wild Wings to buying three sodas for the price of one, here are 20 loopholes people used without getting caught.