I am not suspicious of activities at my local High School. I also don't got to Chess Club to watch those practices either. I don't go to my sons Boy Scout meetings either; simply pick him up and drop him off.
The problem is that most parents are to some degree living through their children. They don't need you at practice and or tryouts. Go home.
It is great you live in a world where you can blindly trust your kids welfare to people you do not know. Most people are not so fortunate to live in such a utopia.