That is right, If I need money, I would work for whatever wage and whatever job I could get. That is why I stayed on for about the last 5 years I worked. When I retired, I did not need the money so did not work for what I was offered.
The plant I worked at was paying in the top 5 in the county when I went to work for unskilled labor. They had to pay that because the plant required working rotating shifts and weekends. At that time jobs could be found many places. They would hire about 20 people at a time ( there were about 2500 hourly workers in the plant) and in 2 months there might be 3 or 4 of them left. It was a very good place to work except for the hours. Times got tough in the last 20 years and the plant even gave a 10% pay cut about that time. The only reason most of the people that were left (only about 400 people on site instead of over 2500 ) are still there is they only have a few years to retirement or they can not find a job anywhere else.
Lets say that doctors or lawyers could be found every where, their pay would drop. Do you remember when you could get the doctors to come to the house for a few dollars (which is probably near an office visit is now) ? The medical schools for doctors and nurses only let so many in now. That keeps the supply down so the demand is up.