Nursing and teaching are surprisingly well-compensated fields with lots of job security and relatively straightforward entrance requirements. It's also true that both fields are valorized, but plumbing isn't and has the same dynamics. These arguments are all overdetermined.
This depends wildly on the country, but in many, public school teachers are criminally underpaid.
Nursing is also a hard job where the paycheck is nowhere near what doctors can earn.
That may be true elsewhere, but not in the US