Because as a straight woman I've heard many of people say that "all women are a bisexual" and I also had my Ex looking a threesome with another woman because he thought I was bisexual. I do know that some straight women watch lesbian porn but then in my opinion I dont believe you are straight if you get off to it and then these women will say things like "but even straight women are attracted to women".
Lol I wish that I was bisexual cause I cant stand men mostly and I prefer female company but womens bodies just dont turn me on especially minge which I really dont know why men are attracted to it