I think it actually is a value difference, just like Blueberry said.

I do not want to participate in nastiness (loosely defined). It's related to my inclination not to engage in malicious gossip. (Folks who know me personally consider it almost weird how uncomfortable I am with bashing people, singly or in groups.) It's not my business to stop other people from doing it, but I just don't want it as part of my life, because it's corrosive and makes me unhappy.

To refine my own position a little bit -- I'm happy to consider anti-PC issues as matters of fact, but I don't like them connotationally, because I don't like speaking ill of people when I can help it. For example, in a conversation with a friend: he says, "Don't you know blacks have a higher crime rate than whites?" I say, "Sure, that's true. But what do you want from me? You want me to say how much I hate my black neighbors? What do you want me to say?"

I don't think that's an issue that argument can dissuade me from; it's my own preference.