Actually is what it is by the way.  Sociolgogy.

Men are grown up tieing their esteem towards sleeping with more women. 

Women are taught the opposite, that protecting ones chasitity is more important. (Yeah, that's generally still the message, despite society.)

Men are supposed to be chasers, and women are supposed to be the thing men chase.  Or at least that's what sociology teaches us.

So to the average guy, being a woman would essentially be like having your goal come to you.

It has a lot to do  with the Male Psyche, physical builds, and Social manipulations.

-Men are naturally steered towards spreading their seed as much as possible. The male lebedo is always in hyper drive. High levels of hormones cause men to think about sex all the time. Also is what cause most men to be more agressive than women.

-Social studies depicts that Men wear sex as a badge of honor while women are conditioned to feel shamed by it. Women do want sex almost as much as men but the responsibilities that are attache with female anatomy hinder them. Women are the "Gate Keepers" or "Goalies". This creates a balance of Men constantly trying to score while women defend their net.

Also consider this...

-Men stereotypically do 2 things when first being introduced to another male. They somehow usher in their sexual prowess(Usually embelished at least a little) and also tell stories of their machismo(Battles, feats, etc). This is used as a status marker. It is a primitive yet some how time resistant way men place their claim for alpha male. Part of this also entails how sexually attracted one is to women, usually quantified in a guy's mind by "how many women can I hit on or comment on wherever I go?". Sometimes this is a constant trope I have notices and if you are me you become highly annoyed by the implecations.

-So by default, whenever this stereotypical male speciman is addressed in reference to women he must respond in whichever direction leans closest to being "pro more vaginal intercourse".

-This is why Men are socially not allowed to respectfully comment on how well another male might look, even though women(who don't have the same inhibitions socially) freely will tell you another girl is cute. This is seen as a counter-action to the male's psyche always leaning "pro vagina" in the never ending score board for Alpha male.

I see this kind of thing all the time. I spend a lot of time watching normal male to male interactions to study this. It is quite useful in daily psychological warfare and personal gain.

We wouldn't exist if men didn't want to have sex all the time.

Thats alittle one sided there are women who are also out there along with guys doing the same thing.

I lol at this very hard, then I found this... 

http://answers.yahoo.com/question/index?qid=20100802003705AAI4P7d

Why?