I'm totally never going to post here again on this site, so this is my first and last time doing so and yes I resurrected and old thread because I believe what I have to comment is important.
One I'm a psychology student and premedical student I've been in school long enough to have my PHD and MD and keep going...
Your sexuality is defined by you. You're labeled however by others and that's based on two things: the information that you share with others or what is readily accessible by your person (ie: Your mannerisms, the way you dress, your hair style, the way you talk). You can say you're straight and have oral sex performed on you by another man receiving or giving , you can have anal sex with a man top or bottom. You define you.
Yes the penis is going to respond to stimuli regardless of if it's a man or woman. There are guys who are curious about it but that's as far as it goes sexuality is rigid, curiosity is fluid.
You cannot make a straight guy want to bone you or have any sexual interaction unless you looked rather feminine like boobs and all. The heterosexual brain looks for cues like hip to bust ratio and that's it if you don't look good then you don't look good.
So you were with 95% of guys who identified as straight because your just not what they want. In the gym all that's there is aggression.
The real problem I see here are gay men who like straight men instead of other gay men, it's weird somehow you've internalized your own version of intolerance even in your original post you've distanced your self from other gay men, as if there is this archetypal gay man that your afraid to become if you associate with them. You're attracted to masculinity which is obvious for gay men some of them adopt a feminine persona because they identify with that and of strength it doesn't stop them from being men who are attracted to men, they've just decided to embrace who they are in a way different from you.
You however are still hiding from yourself and that is why you've posed this question you're attracted to them because you feel like it puts you above them (other gay men) because you don't feel like you're like them, low-key they disgust you because you're disgusted with yourself. I find that to be pretty sad, because when you hate yourself how can you love or show affection for others? Do you even know what love is? Do you even preform well enough sexually?
I think that's also why you're looking for quick casual sex with repressed straight men because you feel like you're dirty. I'm sorry for you and I hope that you come to terms with the choices that you've made in life to consolidate yourself into a complete being.
For TLDNR (too long did not read): Learn to love yourself and embrace the members of your community instead of pushing them away, no one is judging you but you ... because no one cares but you.