The average RN salary is $66K. However, that's just the base salary. Most RN's work some night shifts and some overtime, which can very quickly push that above $100K. In most of the US $66K - well over $100K is a lot of money. It doesn't go very far in the valley, though...

Is that the argument? "street sweepers, waitresses, barmen, firemen, nurses, teachers" should be very highly paid?

Someone should invent an economic mechanism that raises salaries when it's hard to find workers. This mechanism should work in some automatic fashion that allocates money to fields that are understaffed.