I did it too back in junior college. One jerkwad even “tried’ to pay in monopoly money. Another paid IN COINS (pennies) to reach $21.
The most interesting was delivering to a gang neighborhood which I hated. One times I did which was a meeting between 2 Asian gangs, everyone was packing heat and they tipped handsomely like $20. One of them even gave me a 6-pack of Heineken for delivering on time...