In my area yes. Zoned schools exist but the rules allow for finagling.
Private schools is an arms race to who can get more football players in the building.
Some. Not all. Don’t paint with such a wide brush. I would argue that the disparity between private school athletic emphasis is similar to the differences in culture and emphasis you see in public schools as well.
“As to methods there may be a million and then some, but principles are few. The man who grasps principles can successfully select his own methods. The man who tries methods, ignoring principles, is sure to have trouble.”-- ---Ralph Waldo Emerson apparently would have been a great football coach!