How do idiots find each other?

Stupid people shouldn't breed. I see this every day. How do these nitwits find each other? Is there a handshake or does some dumb woman find a guy and say "gee, I'd like to have kids with this unemployed, drug-addicted looser." Then, they realize that this looser isn't good enough, and they go find another and have more kids.
My daughter came up to me a few days ago and said "Mom, you know, you and Dad are really weird." Since she's a teenager, I was ready for this, or so I thought.
"So, how are we weird?" I asked her.
" You and Dad are married, you had all of us together,not with other people, and you got married before you had any kids"
What kind of world do we live in where the natural order of things is weird?
Not that I am slamming single mothers OR blended families. Sometimes marriages or relationships don't work. What I have a problem with is a casual-sex mentality that has many of the women in my area having families where there are 3 or more dads, and Mom doesn't get any money or support from them, and keeps choosing the same kind of man. Things like this make me think my Dad's worn-out saying of "Why by the cow when you can get the milk for free" has some merit. It used to be that a guy had to show some character, have a good income, and be able to support a family to get married, and since you had to get married to have sex, you worked towards this. Now, since the sexual revolution, all you have to do is be somewhat compatible and you get laid. Most of the time there are no complications, but lots of times there are. When you put sex before the relationship, you have nothing to fall back on when these things happen, be they babies or STD's. What's really scary is the amount of pregnant middle and high school girls there are around here. The reason, so I'm told, is that there's nothing else to do.
Back to how they meet. Do their dealer's introduce them? Do they meet in court, or at the drug testing center? Do they share a parole officer? Or is there a place they all hang out that the rest of us don't know about? any ideas?