The use of seat belt is now part not just to the person that is driving, but also it is useful for the other people in the car and in the other car that it is crushed.
The seat belt not just save much more lives, but also prevent in-volunteer homicides like the ones in which the driver has the fault to kill another person in another car.
So now, the people is aware not just what is going to happened inside you car, but around it. That is the way how the norms or rules surround the society depending the needs of it.
