Have you seen all the cuddling in mma?
More than care to admit it, I'd bet.
I personally wouldn't want to know if the guy I was getting in there to fight/wrestle with shirtless, etc., was gay. I would rather not have that on my mind, or else I'm just gonna try to keep it on my feet and tap as soon as he gets the back mount. I don't wanna see mma matches end in a 'happy ending'.
Honestly though, I bet there are many more out there that are gay in personal lives but wouldn't come out with it for the sake of not being outed in the sport. It's a business, they have money on the line and it's always wise to keep personal details/sex life private and away from business affairs, no matter what the case.