I think the bigger point, which has been glossed over by three people now, is that "he could afford it" because he taught there. Ask most people in upscale neighborhoods why they send their kids to the local public school instead of the local private school, and 9/10 of them will include "cost" as part of the equation.
Nope. Almost none do, actually. Generally they don't see "the loacl private school" whatever the fuck that means (it's apparent, incidentally, that you know zero parents who live in wealthy zip codes...unless you count me and Nexa, I guess) as better in quality or they'd send their kids there. A fair amount of them send their kids for additional school work, Kumon or whatever, so they're spending the money on it, just not on private school. Because public schools in wealthy zip codes are generally fantastic, send a lot of kids to tier 1 universities, etc., and the parents and communities can fund programs you don't see at other public schools. Our town swim and diving team is nationally ranked, and the golf team was the best in the country a few years ago.