Teachers apply knowledge, experience and work in a way that magically makes you smarter and informed. Their effectiveness is a measure of their skill and the students. The argument against the unions is bunk — paying a premium for a math PhD to teach high school is probably pretty dumb... experience makes you effective at teaching trigonometry, not PhD expertise in math.

Go to any catholic school and you’ll see woefully unpaid teachers doing an amazing job — because the parents and therefore the students are very motivated.

The discussions about developers are similar. You need to overpay for people in a few metros... but you can pay a lot less for skilled people all over the place. The wacky salaries in industry have more to do with control and investors than the actual work.