In my experience, most people who throw around un pc words aren't out there raping women or rounding up lynch mobs. But then there are those few people who use humor as a way to cover up genuinely hateful personalities.
It's important to differentiate between people who take political correctness to unnecessary extremes, because there are a lot of them out there policing language and being annoying, and people who just don't appreciate bigotry. For example, a lot of social conservatives talk about political correctness as a way to justify teaching their children that all gay people have something fundamentally wrong with them. I don't want anything to do with people like this and, if this makes me politically correct, oh well. I'm secure enough in my own beliefs that being unfashionable is not too disconcerting. Again, it's very context dependent since words and phrases are only as meaningful as the way they're used. I doubt the majority of people who complain about political correctness here are bigoted, though. I have some pretty violent artwork that many would interpret as misogynist, but I know where I'm coming from is very different than their interpretation--so PC people get on my nerves sometimes too.