In Britain, the private boarding school system functions in a similar (and in fact more extreme) way. It's odd, because in Britain the obsessive approach to national and personal identity, to shaping what narrow category you must conform to, and actively traumatising you if you fail to comply (or in may cases even if you do fit in, but at huge cost to your own self-image), is confined to the privileged few. Whereas in the USA it seems to have been distributed across the board through state schooling.

Both British private boarding schools and US high schools might tick many of the boxes which one would use to define a cult.