> By definition, a person who is working only because he must will not get a fair wage. One side has leverage, one does not. So the worker gets screwed.
By the same definition, a person who is hiring because he must also will not get a fair wage. He needs to get the job done, so the laborer can charge him an unfairly high price.
Of course, it doesn't work that way. While a person needs to work, he doesn't necessarily need to work at your job. And while an employer needs a job done, he doesn't necessarily need you to do it.
Wages are fair in a free market because workers hunt around to find the highest employers will offer, and employers hunt around to find the lowest laborers will settle for. The result is a nice compromise between the lowest people will work for and the highest people will pay.
Do you have a better definition of what would make a wage fair?