Watch the video, taken by an amateur in JFK, of an AirFrance A380 touching a smaller plane and spinning it around and imagine you where sitting in the small plane not buckled up:
http://www.bbc.co.uk/news/world-us-canada-13054205
The reason why this behavior mystifies me so much is that by jumping out of your seat prematurely you will be leaving the plane exactly 0 seconds earlier as when you remain buckled up until the plane is safely parked at the gate.
http://edition.cnn.com/2013/06/05/travel/sg-airlines-turbule...
or
As soon as the plane lands, there is a tricke of clicks until the plane is parked. And when the "fasten your seatbelts"-sign is switched off, the rest of the passengers go "click". From my experience, this sounds like most of the passengers.
(My experience is mostly from Norway and Europe in general)