do you tip at resturants?

My Dad got hacked off at a waitress who was lousy and ignoring him. Even when she walked by and he called for her she ignored him. He left her a penny tip. On his way out the door she threw it at him and hit him in the back of the head. He said he just kept walking like it never happened laughing. He was kinda ornery like that.:-D

It'll be even funnier when the penny is extinct. I can't wait I have a ton of pennies at home and servers will love getting worthless money.