The answer is maybe that we're DNA wanting to be eternal so to us to have children with still that DNA, etc. We are like the spermatozoids.... and the DNA is the eternal thing... since billions of years ago.
But as we can trick this with contraceptives... it's somewhat different. But still we're attracted to people that would fit our DNA best to reproduce, etc. even if we don't want kids at all!. It's on our DNA. So we still behave this way. We behave like if we wanted to have a lot of children or so when we mostly do not want it. That makes us want to be loved, rich, beautiful or whatever...
We're quite pathetic... DNA does what he want with us...
