Well technically you can use racial slurs all you want, the only thing stopping people, is the social circles around them's willingness to accept such behavior. Or if you are a media figure, loosing your job.
If it was me, I'd rather know they were, than have them hide it, at least I would know who I could trust. And I think once exposed, its a problem that could be better dealt with. Instead of teaching people just keep those thoughts to your self, and let your racist, sexist, ways come out more passively. Which allows people to constantly be suspicious about other peoples motives and causes a lot of tension between people.
Though admittedly, getting people to stop needing some other group to put down, so they can feel better about themselves, is not ever going to be easy. Its a shame, in the "survival of the fittest" certain members of the species, find it easier to hold people down, than excel at it themselves. But we are what we are, and have been. At some point in our history there may have been a point to all this, but not anymore. Maybe it made more sense when we were doing these things over food, because there wasn't enough? Who knows.
I think its more effect to actually talk to people about why they think this way, what caused it. It was socially acceptable when they were kids, some one picked on them, stole their girl friend, cultural conflicts, etc. Getting to the root of the problem, than just telling them, you can't say it, but keep on thinking it.
