gurey,
I think its because women by nature are more tolerant and in this particular case perceive gay men as being non-threatening. Don't forget women are usually self-serving. Gay men to them are like a male version of a girl-friend; they know he'll never make a move on them, he'll be there to lend them a shoulder when they need one, will gossip with them, talk fashion with them, will never rape them or take advantage of them, etc. At the end of the day, its about watching out for their interest. Gay men offer them a sense of security they can't find with hetrosexual men.
Also, because women are different than men in terms of their psyche. That's why they're more open to lesbianism and don't see a big deal with girl-on-girl action.
I was reading this article a while back, maybe it'll help:
By contrast, women may be more open to same-sex relationships thanks to their less-directed sex drives, Bailey says. "Women probably have the capacity to become sexually interested in and fall in love with their own sex more than men do," Bailey says. "They won't necessarily do it, but they have the capacity."
Bailey's contention is backed up by studies showing that homosexuality is a more fluid state among women than men. In another broad review of studies, Baumeister found many more lesbians reported recent sex with men, when compared to gay men's reports of sex with women. Women were also more likely than men to call themselves bisexual, and to report their sexual orientation as a matter of choice.
http://www.webmd.com/sex/features/sex-d ... are?page=2
Cheers, mate.