heh, I guess until male bisexuality (and gay love in general) is not considered an 'unmanly' act but just a sexual preference we can't expect it to be included if not in specifically tailored games. It's so weird to me how a lot of straight guys when I state I'm bisexual immediately jump to the conclusion that I want to sleep with them; hell, surely they don't want to sleep with every woman they cross despite being heterosexual! Hold that thought, that may exactly be it...
As a side note, I'm sure there would be a lot more bisexual guys out there if they just experimented; poor sods, don't know what they are missing!