Probably because they deal with young children and teenagers who don't listen to them.
I remember during my middle school years in 2009-2012 (I was born in 1998), my school bus was considered ghetto and had fights, yelling, stuff being thrown around, etc. and the bus driver, this old Latino/Hispanic guy by the name of Nick, couldn't get the twerps to stop.
But by high school, oddly enough, the once ghetto middle school students, where no longer ghetto, as they either matured or likely where too tired from waking up early to have the energy to act like a juvenile delinquent. Good times, good times.
Based on a true story.