I hate watching rollovers, especially when the person is not being a yahoo. But you can learn a lot by watching the physics involved in videos like this one. The people not wearing seatbelts are an example of the power of centrifugal force. Even in low speed rolls people can get ejected due to centrifugal force. It is very easy to be severely injured or killed by being crushed by a rolling vehicle when a person is ejected or partially ejected. So as Mike implied, wear your seatbelt and take responsibility for your passengers and make sure that they wear their seatbelts too! Vehicles can sometimes roll in seemingly innocuous situations so always be prepared and belted in.