I'm sorry, but the in three years I spent working at Walt Disney World, one of the things that they did not tolerate was being rude to guests. You didn't have to take any abuse, but you certainly were not allowed to be rude or give the impression that you had an attitude. If you did you were gone. Didn't matter what you had going on in your personal life. And, yes, I had to interact with more stupid people on a daily basis than you can imagine, answering the same stupid question about 200 times a day if not more. It didn't matter.
That's what I expect from whomever I am dealing with as a customer. My personal problems don't give me immunity from being polite.