I would call it being over-sensitive, because a little thought and work would discover exactly what The Onion was like. Objecting to this would be much like people who object to the use of certain words under any 
 circumstances (like "fuck off") when they are merely used a colourful way of saying "buzz off". The automatic use of a list of word to block someone means that us admins are not doing our jobs carefully enough, since we could be simply replaced with robots if that is the kind of way we operate in this case. Think "Turing Test".