No one is sitting around and setting salaries based on the intrinsic human dignity of the people working jobs.
Bigger problem in the SF area is that a bunch of folks who owned property before the gold rush have ended up real-estate-rich, and formed a voting block that actively prevents the construction of new housing (on the basis that it might devalue their accidental real estate investment)
Besides, I did already say that everyone else was underpaid relative to costs. But that's not unique to the Bay Area. Cost of housing relative to income is terrible in almost all of the major European cities too.
Once cities become wealthy enough to develop a home owning class, they seem to cease being able to provision adequate housing supply in general.