Anecdotally, the handful of furries I've known in meatspace were all bisexual, and I suspect there's a correlation there - if your tastes are broad enough to include humanoid animals, then they're more likely to also include both genders.
Similarly, all the perverts here who enjoy (insert extreme kink here) also tend to enjoy, or at least tolerate, (insert unrelated kink here). Look at how many mind control games end up focusing on family members, for one example - if you don't mind one taboo, you're less likely to mind other taboos.