I’m families with the competitive nature of high school sports, particularly at the higher level. The school board probably has a say because the private school plays public schools. If the private school doesn’t obey their rules, they can’t play.
Public school students rarely have a choice of what school they can attend. And if a student moves, particularly an athlete then school board look very closely at the situation. On of their inspectors came to my parents house after we moved because by younger was a starter for a larger 5A school.
So it’s a serious issue cause schools will do anything to get star athletes and there is cheating involved everywhere.
BTW: we did move so my brother could go to that other school. Lied our a** off to the inspector. He later got a football scholarship, me academic. :)
Your first paragraph is based upon a misreading of my example. I said the private school doesn’t have a team.