It's to prevent the game from allowing things like: "Fuck Niggers, Kill Them"
That is pretty funny though.
And I wouldn't consider it censorship. It's their product you use under license.
If a company tries to hire you as an employee and says, "Hey, we'll pay you $70,000/year, but you have to wear a dress." And you say, screw that I'm not going to do that, then you don't have to work there.
The same thing is present here, you don't HAVE to play the game.