Well duh, they would lose all their new references if we started making some.

From a legal standpoint, I'm sure that covers their ass. If you make a character that's offensive to someone (say, Paris Hilton as a male gnome or something, idk) and there's a lawsuit they can say, well, we didn't want anyone to do that. But they can make Haris Pilton and control the context of it (they don't, for example, make her do anything really embarrassing or awkward that Hilton would find offensive, its just a silly joke.) Maybe Hilton isn't the best example because she's not all that controversial, but if you were to make, say, Bush or Obama and stage a torture roleplay in Dalaran, you might quickly find a situation that's offensive to people and might cause a lot of controversy.

It isn't hypocritical at all. They can control the jokes they put in, they can't control what you do with their game. It makes sense for them to put disclaimers like that in, and remove things that are immersion-breaking even on non-rp servers.