Guess it slipped by them in the 90's. Considering kids did read Mad back in the day, I'm surprised they used it in the first place.
Of course, we now live in an era where "schmuck" is bleeped out of old movies on tv. (Pretty sure I first saw that word in Mad, if not Cracked.) It only took the self appointed guardians of decency 40 years to look up what it means? ;)