This is also true with women.  Many of us have sex merely due to physical attraction and some due to the guy having money too.  Many women have sex with men they are not in love with and some with men they don't even like all that much.  Sadly, men are not the only jerks that exist out in the world and use sex for completely self-satisfying reasons.

The one thing that is different is most women do not resort to raping men.  That is probably because it is more difficult to force a man who does not want sex to have it but that is not true with female anatomy.