Weapon X shared an article that anyone who have worked in the food industry can understand. http://www.violentacres.com/archives/59/two-phrases-that-destroyed-american-culture/
^^ My old manger was like that. We worked in fashion retail and had to deal with the moaners of the world every day. Lol, she was brilliant. Took no shit off the customers.
Managers today are too scared because anyone can sue anyone over anything.
I managed for a retail chain in the mall (Suncoast where by Gods the customers were friggin dumb and mean) and for mom and pop video stores and never once let a customer behave that way for long.
The key is to remain calm, friendly, and keep two things in mind: fairness and reason. This is what I told my employees and I always backed them up when a dickhead started shit in the store.
If you always play those cards your behavior will so thoroughly irritate an already irritating asshole customer that they ultimately realize they are not going to win OR they realize they are publicly embarrassing themselves and will stop and/or go away.
I used to live for the days when someone would say "get me your manager!"
I manage a Chick fil a and I love this article I have to deal with assholes on a regular basis who I am forced to be polite to and I would much rather cuss them out and send them on their way.
God forbid if I'm ever industrious enough to be managing others, I will totally be the guy to say, "How dare you treat my employee that way, get out." (Probably means I won't be managing long.)