Seat belts on busses

I've started taking the school buss and I've never seen anyone wear a seat belt on one. I mean I don't wear one either but does anyone know why no one wears a seatbelt on the buss cause I don't because everyone else doesn't, I'm a copy cat. I've never seen a single person wear a seat belt on any of the busses I've been on, some people even sit sideways in the seats to lay down.