Why Do Some Terms Upset Otherwise Ordinary People?

I've never seen anyone use the term "please and thank you" when they weren't a jackass, douchebag, or dildo, midway through the process of actively being a jackass, douchebag, or dildo.


I don't know what it is about that phrase...although I sort of do.  It's like it simultaneously acknowledges that there is such a thing as manners and civil discourse, and then tosses that concept back in the listener's face.  Like they're saying, "Sure, I could say 'please' and 'thank you' like someone who went to Kindergarten in the Western world and had parents moderately interested in teaching me decorum, but instead go fuck yourself."


I dunno.  It just really grinds my gears.  Perhaps it's because I've never heard it in a genuine context.  I mean, maybe it defies being used genuinely.  It always seems to be something people use in a sarcastic manner.


My roommate in college couldn't stand the word "breath."  I didn't understand that.  I mean, I sort of do.  Breathing is vaguely related to germs and certain kinds of breathing can be sexual.  So, okay, just the idea of breath was bothersome enough to him that the word itself upset him.  "Please and thank you" might be my "breath."  Or you might all agree with me.


What about you?  Any terms or phrases or words that just get your hackles up?  Justified or otherwise?