Well, its probably easy to have kids with a large number of women if you actively include 'poor choices' relative to your social standing. Seemingly most people want to move up or at least stay equal in social ladders when it comes to the choice of a mate.

Human beings are weird in that "failure to integrate into society" and "failure to pass on your genes" don't necessarily overlap.

In fact, failure to integrate into a social order often increases your chances of passing on your genes.