In all fairness, Americans at that age (18, fresh out of high school, away from home for the first time) have a global reputation for “partying” instead of learning. We would prefer greater studiousness and piety from our children, they do behaive a lot better than the goyim the same age.
Arguably, they would be better off staying at home with their families, but children that age think they are grown up and are restless to leave home.
Traditionally, this is when they got married. They are too old to be children in their parents’ houses.