C'mon, how many of the Field medallists were doing maths in order to earn as much money as possible in order to get a bride? (I agree that that's probably what's going to happen in the medium-long term, but for different reasons.)
I remember one ha-ha-only-serious from my mathematical days: Sex is just a sublimation of the urge to mathematics. (And it's long been observed that even among young mathematicians, their output falls off dramatically if and when they marry).
Dalrock writes an interesting article related to Dr. Helen Smith's book the Marriage Strike. I really have to bump it up on my too rapidly growing reading list. (^_^)