I think that the traditional family vacation has shifted from the two-week vacation with a plane trip at the beginning and at the end to a lot of shorter vacations throughout the year.
There's ... a liability issue. If an American Airlines plane hits clear air turbulence and someone is injured, they can fall back on the fact that they have it stated in their policy that they must be seated with their seat belt fastened at all times.
Once everybody gets on the plane with few bags, once the plane lands, getting off the plane is a lot easier.