Frankly, I could care less.....except for the fact that if we hit turbulence the "floor sleepers" are more likely to be the ones taken off in crevical collars. In addition, I don't want someone not wearing a seat belt landing on me after they bounce off the ceiling.

A friend of mine, an engineer at Boeing, says that they have a saying about people on airplanes (and turbulence):

There are two types of passengers on airplanes:
Those buckled into their seat and projectiles.