There is a general rule in land based casinos that a gambler shouldn't take credits left on a slot machine by someone else. Basically, from what I understand, if there is still credit showing on a slot machine. Don't cash out or add to your money you put into the machine. Right? The question is if you find a cash out voucher resting on the machine itself or on the seat, can you legally use it?
Unwritten official rule inside the casino premises that never take those vouchers not unless it's clear that the previous player intentionally left it.
It's just that if these vouchers are ignored, other stalkers will likely take advantage therefore just go with the flow and have that to ourselves. Some staff are serious about looking at these attempters but there are staff that just allow those stalkers to look for those vouchers as long as they are not creating a serious problem inside the casino.
If no one is looking, someone can take that voucher, and used it like nothing happened lol.