[danielweber]

That's a specific case where their client base literally does not care about the cost. $30,000 or $40,000 makes no difference to them.

Or, to take it further, it's quite likely a Veblen good: because only families that can shrug at $30,000 a year for private school will be going there, your kid will only associate with other rich kids, creating valuable romantic and professional networks.