Well, my 0.01:
I've heard many friends (male) say the following sentence, meaning that they like sex very much:
"If I were a woman I'd be a whore"
OK. My sentence is the following one:
"If I were a woman, I'd be lesbian"
I think I have some reasons for saying this, since I have some gay friends and some lesbo ones, too.
Think something: we men are very limited in sex. We can do our best to please our partners, but whatever we can do, our last satisfaction is an orgasm 8-10 seconds localised on the "red end" of our "instrument", and after that we need a while to recover.
We certainly can intensify our pleasure by manipulating other places during the orgasm, and get an orgasm twice as long and more than twice as intense. But women can go on from one orgasm to another almost continuously for as long as they want or do not get tired. And be sure of something: two women making love can reach to levels of sensibility, sensuality and pleasure that we men can hardly imagine.
For our luck, most women try to refuse it in their minds, too. Because, otherwise, we would have very difficult time finding female sex partners. You can swear it.
The reason we prefer lesbian sex rather than gay sex has been clearly written above by Swissgabe: as we do not please sex with other men, for sure we do not feel attracted by two men "doing each other", regardless it is for their own satisfaction or for $$$.
But I would like to note something on Rindt's sentence: you can bet your sexual orientation that there exist some of what some friends and I call "truck driver" lesbians, but most of these ones are frustrated on other aspect of their lifes, mainly their own body or beauty standards.
On the opposite hand I would be very pleased to introduce to you some stunning beauties that would cause either that:
1.- you accepted to pay crazy amount of money to have sex with them (provided they accepted, which would be highly improbable), or
2.- you committed suicide because they would never accept any kind of male contact, or
3.- you became gay thinking that your future as a "chick conqueror" had come to an end, or
4.- a combination of the previous ones
Finally, the comment of SEVEN_FIFTY7 about some lesbians being "confused bi-girls" is somehow correct, but I can swear that the many most of them are confused for the OPPOSITE reason: they are young, they feel lesbian, but because they doubt, they tend to refuse one of their orientations. And because of social "rules", they try to refuse their lesbian part, while actually they are willing deeply in their souls to refuse their hetero side and freely love only "the lesbic way".
BTW: I haven't read any comment from our female colleagues, so far. What do you think? Are any of you lesbian, or are you willing to become lesbian, or have you ever thought (even only once) to make love with another woman? Many women without prejudices that have "crossed the line" have never come back... And some of the ones who have come back have done it because of social reasons but/and/or keep a secret lesbian lover, or have even managed to convince their male partners to participate in trios with other women (which is not that difficult, since most of us have the fantasy of having sex with two women, and whoever says the opposite thing is lying).
Just my opinion (based on some facts)