The sports-parent and coach lobby in high schools is often one of the stronger interest groups. I've known teachers to advocate for later starts in meetings (again: it really, really isn't due to some powerful cabal of ordinary teachers who just looooove starting school incredibly early) and be told sports are the reason it's not gonna happen (plus having to re-do bus schedules—admin hates working). Also, I can report that the old trope of high school athletes getting grades adjusted or being given way more leeway on disciplinary issues, which one might hope was now only observable on retro 80s movie nights, is still very much a real thing. Most teachers hate that crap, too, but administrators, coaches, and sports-parents all like the preferential treatment for athletes.