It is even true in the academia. This paper describes research using data from New Zealand where academic salaries are the same across disciplines. Each discipline, however, can command a different salary in the private sector. Not surprisingly, the authors found that disciplines with higher opportunity costs attracted less talent. The authors state...
disciplines in which the fixed compensation is high relative to opportunity cost are best able to recruit high-quality researchers and/or motivate their researchers to be productive. Paying (relative) peanuts attracts mainly monkeys.
At universities, keeping costs low is simple. Keeping costs low while maintaining high quality faculty is more difficult. I think the moral of this research is that if your faculty salaries are not determined by market forces (both across and within disciplines), and are instead set by tradition or arbitrary rules, you may end up with monkeys teaching your students!
Note: I just thought this was interesting. It is not written in response to any actual event.
