[EricH]

Originally Posted by IndySam

Will the enforce this any better than no seat saving?

It may be a little bit easier to enforce. It's a little more obvious when UFOs are spotted airborne. Identifying the originator(s) may be a little less easy than spotting violations, but a couple of announcements of "Will the persons throwing paper airplanes from Section XYZ please cease and desist before event staff arrives to enforce cleanup" ought to do the trick.