Evil Customers Classification System

I can occasionally have a post about something I don't know anything about, right? Thanks for the permission, as though I needed it. Ah what luck! A subject I don't know anything about: evil restaurant-customers. I've never been a waiter, and if the Fates don't hate me, I will never be a waiter. This webpage acquits me of snobbery by detailing a number of different classes of evil customers; as a bonus it's funny and includes the tips you will receive from them (which unsurprisingly are usually very low). Now we just need something similar for evil checkout-customers... I'm sure I came up with five to ten types during my days as a Customer Assistant [a period which proved beyond doubt that the 17th year of life can not be classified as being amongst "the best days of your life"]. CUSTOMERS