Kids: maybe I'm foolish, I want my kids to grow in China. The air is bad but they will respect their teacher and elders, they will be able to safely walk in any streets, they experience a fast changing and exciting environment, with friendly and welcoming neighbors, and maybe most importantly they will be well equipped mentally and culturally to understand the world all the kids of their generation will have to live in.
All of that is obviously weighting much more than air considerations.