Dear Lost,
What do those that do wear a hat think about those who do? If they would feel betrayed, than there is a communal issue here. This type of issue seems to fester in all Jewish communities today. And is very difficult to bring into the light, and was never examined thoroughly.
There is no range or benchmark when to wear a hat. It is a personal choice. I see that a lot of fathers who took of their traditional garb put it back on when they have their boys going to shul with them. (Boys old enough to daven. Even on late Friday nights.)
If you feel that all your children will settle in the major Jewish centers of the northeast (or it’s satellites) than it is useful to assume it for them. But if you see your family as being more diverse (like mine) then a minhag that is in conflict with the family structure and setting seems unwise.