Why would you want to belong to a group of people that commits such horrendous acts of sexual deviancy and deprivaty? Grown people fucking each other dressed up as animals, some even dying in the act. Suffering strokes and heart attacks because they so badly want to know what it's like being a dog shagging another dog.
This is a group of people who call normal, healthy people "mundanes" and apparantly look down on them. Sometimes yiff can get gross, you say? Name me one situation in which it isn't and you get a hundred bucks.
I think you're overreacting too much with that.
Now, to the question "why so many furries are gay/bisexual" or whatever was the question, i think it has to do with the porn (no shit bro).
Ok, let me explain, i have nothing against people watching porn, as long as it is not something fucked up like child porn or animal porn... then, why i can tolerate furry porn? honestly, i see it the same as i see the fetish for elves and things like that, i don't see it as offensive or fucked up, when they don't stress the animal features that much, it can come as the fetish for anime cat ears...
Back on topic, there are lots of misogynistic gay men out there, (just like there are lots of misogynistic straight men and whatnot) and the only way they can express that, is by joining a fandom that has a lot of misogynistic gay men on it, so they can relate to them, now, that is fucked up and disturbing, i know.
Honestly, i don't know how to explain it, because it's a really weak theory just like the rest that i've read here, it sounds silly, but it's really hard to state a simple fact that answers that question, is just like asking what is the relationship between wizards and mlp, or autism and sonic.