It does that already. But one can't deny the danger of demagoguery designed to inflict actual damage on identifiable groups.
Hurt feelings don't count, of course, or at least, shouldn't. Be as offensive as you like and I will be offensive right back at you. That oughtn't to be an issue.
You understand when there are radical groups that rise up or already have risen up, police usually start investigating it immediately (especially since 9/11) to keep an eye on them. If they were to start planning attacks on blondes, their plans would be stopped immediatly.