Hoofers is another nickname given to bronies. This meme originated as one of the questions in a game of "Who Wants to be a Millionaire". The question, even for outsiders of the fandom, was pretty blatant, and the other three multiple choice answers were just silly.
Question: "The children’s TV show ‘My Little Pony’ has found a large following of adult male fans that are known by what name?"
The words, "Mare-men" and "Man-colters" just sounds anthro-mythical creatures but the word "Hoofers", honestly doesn't sound as bad as the former.
Hmm, you just have to ask yourself, if you went back to the original thread on 10/25/10 to change the name..."hoofers" would probably be the new name.