"Grocery Shopping" joke

A man entered a bar and ordered martini after martini, each time removing the olives and placing them in a jar.
As soon as the jar was filled with olives, and all the drinks consumed, he started to leave.
"Excuse me," asked a customer, who was puzzled over what the man had done, "but what was that all about?"
"Oh, nothing much," the man replied, "my wife just sent me out for a jar of olives!"