Biteme, it is because it is a word that incites hatred and tremendous disrespect.
It is no different than NIGGER - SPIC - WOP - WETBACK - RAGHEAD, etc.
It is demeaning and degrading, not funny at all.
Some women may not take offense to it as some men might not be offended it you called them any of the derogatory words mentioned above.
How many times does this have to be said on the boards for just a handfull of MEN to *get it*?