I always manage to get stuck in the exit seat when I travel. I guess that can be a good thing, but not on every flight. I travel by myself a lot, so I am seen as young and able
I have been on a flight however where a couple had their 2 infants sitting on their laps on an MD11 exit row. Totally illegal and irresponsible, but when a passenger knows someone at check in, you will find that the agent blags all the rules.
Generally they will look for young males who are travelling alone to sit in the exit rows, and they give the bulkheads to parents with children.