Yes, lol. One time, I had went into store to buy something for my sister (she sent me in with some money), though, when it was time for me to pay for it, the money she gave to me wasn't enough!
Ah, I told the cashier I would come back with the money, but a man nicely put the rest of the money in.
It made me do the same for others, even my sister who needed extra money once.