I hate to sound cliche, IAKG, but I think the reasons are the usual ones. Guys are more visual, and are generally more interested in seeing a woman naked than men seeing a man or seeing a man naked (note I made a distinction there). There's ALWAYS more demand for men seeing women than vice versa, though I think the tide is changing as women are being allowed to be more sexual and express themselves sexually.

Thanks for the comments guys. I guess I'll see how things go.

Nice to get a real conversation going however.