And my honest opinion is that any parent who books a seat to save money instead of one that guarantees they sit together is a bad human being. We all get to have our opinions.
You actually can't fathom that not all families on an airplane are going to their DVC resort to have a 10k vacation? Poor people fly too, poor people have kids. People fly for reasons that aren't even remotely fun like vacations. Like back home to a family emergency, to a funeral too far to drive, etc. It's funny, I briefly worked with a guy who thought people were terrible parents if they couldn't buy their child a car when they turned 16, he actually said "you shouldn't have more kids if you can't afford to give them everything in life". It made me feel better at the time to think he was some anomaly in the world, but clearly he isn't.