Those lines were part of Chapelle's skits, they were clearly a part of a joke. Michael Richard's rants weren't a part of a show or routine, it was just him shouting at a patron. It's not because he made comments about blacks, jews, or any other race. It's because there wasn't any satire to his statements, and they seemed genuine (or it appeared that way at least).

I was just pointing out that it wasn't anti-semetic remarks that got Richards in trouble, it was disparaging remarks against blacks.

Edited the above to make that clearer.