[ZenGum]

I know of a *FEW* professors in the US$250,000+ range.

Very, very few. Generally, some cashed-up US (often, but not always, Ivy League) college wants to raise its profile in some particular area, and decides to poach an entire research program en bloc from somewhere else.
Back in the early '90s, one US college (I think it might have been Bowling Green) offered four Profs. from the Australian National Uni Philosophy program about $250,000 each provided they all came as a group. (They stayed, mostly for family reasons.)

More recently, the Australian government has brought in "Federation Fellowships" which offer salaries around $250,000 and are used for counter-poaching.

Most tenured academics are on less then $100,000; and at the bottom of the pile there are many non-tenured, contract, or even causal workers on mediocre salaries with no job security. Hours depend on enrollments, and these vary year by year.