to all of my fellow servers.

sally: let me ask you something. was your service quick and courteous?
customer: yes.
sally: was your food hot and exactly what you ordered?
customer: yes!
sally: then why is it, my friend, when i subtract your check from the amount on the tray, i come up with 97 cents for me.
customer: i didn’t think you’d count it in front of me.
sally: (laughs) but you’re glad i did now, aren’t ya? because now you understand that a TIP is short for GRATUITY and gratuity is short for GRATITUDE.
customer: i never heard that ma’am.
sally: don’t interrupt me.
sally: gratitude for a job well done. now five percent is not gratitude mister, IT’S AN INVITATION TO AN ASS-KICKING. got it?
customer: got it. (leaves a generous tip.)
sally: thank you!… have a nice day! 

— Sally, 3rd Rock From The Sun