Men and women are really different in their sexuality. Years ago I saw a show on that, and they pointed out how men like looking at girlie magazines while women like romance novels.

Men just like sex and aren't really that picky about who they are willing to have sex with. Women on the other hand are much more picky in that they have to have feelings for the guy. The idea of having sex with some strange man on the street is repulsive to most women (forget what porn shows, it is catered to unrealistic male fantasies).

It has to do with human reproduction, the men have countless sperm they can throw off, while the women only produce one precious egg a month, so by nature they want it fertilized by a special male.