Ignoring all these space marines, however hard that may be, I'm going to say why I dislike furries;
Just like hugely flamboyant gays who shove their loveuality down your throat and expect you to be OK with it and hit on clearly straight men and wear bright clothes and sound like women and wear purses and flail their arms around and foam from the mouth while screaming "OH EM GEE!!!!!!!!", furries are pretty damn similar except for the fact they don't like just men they like men covered in fur (also wimin).
Either furries or flamboyant gays would not bug me at all if they didn't go around announcing it to the world expecting you to be ok with it and then be offended when someone screams friend or FURcigarette and rage and say YOU DONT UNDERSTAND ME! or YOU ARE A BAD PERSON!
Yay this must be my longest post ever :D