I agree that some people are faking it for attention or to be cool. However, sexual attraction and love, are often not cut and dry. Many "mostly hetero" people might occasionally feel sexually attracted or romantically interested in someone of the same gender, even if it's just one person. One lady I knew said she was heterosexual, but she had liked ONE woman before and it was intense. She said it had surprised her, and she's never felt that way about any other woman. She isn't the only person who has experienced that. Also, I suppose it might work the other way around with many "mostly homosexual" people occasionally feeling sexually attracted to or romantically interested in an opposite sex person, even if it's one in a lifetime, or even if it only lasts for a few minutes, and goes away even when faced with the same person later. In my opinion, those people aren't strictly heterosexual or homosexual- they are somewhat bisexual, just not total middle of the road, completely bisexual. You might say they are "MOSTLY" one or the other, but if they are even attracted to one person who doesn't fit, I don't think we can say they are strictly one or the other. Now that it's socially acceptable- and yes, in some places encouraged- to be bisexual, along with the fakes or the confused, some truly middle of the road bisexuals might be coming out due to the safer more accepting environment, while others who are mostly heterosexual or homosexual, but occasionally like the other, might also be more comfortable saying they are somewhat bisexual, but mostly swing one way.

Also, many people enjoy experimenting, and while that doesn't mean they are truly attracted to those people, they might enjoy it on some level, and I think that's okay, as long as you're honest about it and as long as you aren't doing it to meet some societal standard. When I mention the honesty thing, in cases like Nucking Futz, the friend should have been honest about just wanting to try something out. Also, while I don't think women or men should feel forced to touch anyone they don't want to, just to attract someone they do like (in other words, for ex., women should not feel forced to sleep with women just to get to sleep with a man), yet, if a woman doesn't mind sleeping with a woman, or a man doesn't mind sleeping with a man, for ex., and if they are into multiple partners, I don't think it's necessarily bad for them to do something their partner really likes (like bringing in that other party), if no one feels forced to do something that they don't want to do, and as long as everyone plays safe and is happy about it, but they shouldn't have to lie and say they are doing it for themselves.

Anyway, with that said, while I do believe some women and men do it to fit in or stand out (either or) or for any number of other reasons, including (mostly for women) doing it to attract the opposite gender (women making out to attract men), some research has indicated that for women, the lines of sexual attraction might be blurrier on average than they are for men. They showed women and men of various orientations, male and female erotica. Interestingly, while the heterosexual males preferred video of women, and homosexual males preferred videos of men, both homosexual and heterosexual women showed psychological and physical sexual response to the erotic showing heterosexual couples, the erotica showing only men, and the erotica showing only women. I am not saying all women like men and women equally or even close. I'm also not saying that men aren't ever bisexual. I am saying, perhaps more women are likely to experience some degree of feelings for both genders, even if they overwhelmingly prefer one, and perhaps more women, even if they generally are only interested in one gender, might be more likely than men to, at some point in their lives, find themselves attracted to or interested in another woman, even if she's the only one, even if the interest is fleeting.

I guess what I'm saying is, sure some of it is fake, but some of the increase in numbers could be due to people feeling more free to explore their desires, to admit their desires to themselves, to experiment (even if they're not really bisexual, but are curious), and to admit their occasional or long time attraction to members of both genders, to the public.