A guy walks into a bar and orders a beer.

Bartender says, “That’ll be $5.” The guy takes out a huge pile of coins, throws $5 in pennies all over the bar. The bartender is annoyed but picks up the coins.
Next night the guy comes back, orders a beer, then slams $5 in pennies on the bar, drinks his beer and leaves.
He comes in the next night and orders a beer. This time he pays with a $10 bill. The bartender sees his chance for revenge. He goes to the register, counts out $5 in pennies, throws them on the bar. “There’s your change!”
Guy says, “On second thought, give me two beers.”