Anyone who says that women do not act more closely together than guys do has never gone outside. Girls call each other "girlfriend", they hug a LOT, they can cry on each other whenever, they go to the bathroom together (still not sure why that is...), slumber parties (I've actually heard from various women that the rumor that girls sometimes compare breasts at slumber parties is truer that you'd think), and so on and so forth. I'm a little tired right now, so I won't go into detail, but you could probably find the logic train that explains why lesbian porn is more acceptable than gay porn on your own.
Oh, the question was why it's more acceptable for a straight man to watch lesbian than homosexual male porn if they're both gay. The answer: If you're a straight male, you're attracted to women. More women means more excitement. If you enjoy gay, male porn, then you aren't straight, because you're enjoying men. This is a rather easy question, and I have no idea why you have to ask it.
On a sidenote, I actually don't find lesbian porn too exciting. Unless a guy is participating somehow, I myself can't really get into it. There was one porn scene I remember where these two girls were making out, and there was a guy jacking off in the corner. After awhile, he got up, walked to the two girls, and came on their faces while they made out. The two girls pulled apart for a second as cum got all over them, then they both sat back and laughed at how silly it all was.
It remains one of my favorite scenes, if I could find the blasted thing. I haven't seen it in forever.
