Well, the airline industry is certianly an exception in many things, but “market level” would most obviously not be defined as some sort of nonsensical national standard, but an area one; that is, what is the going rate for laborers who do this sort of work? Now, unlike—say—forklift operation, I’m sure many jobs in airports are somewhat unique, though we can certainly make a swift comparison between baggage handlers and, say, UPS employees; ticket clerks to cashiers in general; help desk people to, well, help desk people; and we all know management is the same everywhere anyway, right? 
If Continental decided they weren’t going to pay a penny more than $6.50 an hour for baggage handlers, they (the prospective employees) could go to some package company or general shipping area and get at least a few dollars higher—which, of course, are also unionized, so perhaps you can begin to see that once unions have entered the picture in wages the “market value” of labor loses any real meaning.
In something like fast food work, however, there are largely no unions so we see what unskilled labor generally goes for: about $7 an hour. But even that is a bit of a misnomer, because many union places will hire unskilled labor and provide higher salaries, so that $7 is even affected by competing with unions.
Of course, all that money has to come from somewhere. When an entire industry is affected by something, as the airline industry clearly was here, no amount of striking is going to create money, but the company is obviously locked into the slaries they must provide people. the trade-off then becomes: can we adjust salaries to respond to the labor market, or can we eliminate job stability? Because there’s no free lunch here.
But you knew all that; I know you did. What I can’t figure out is what you are getting at.
Now, the government, of course, has a vested interest in not losing and entire segment of the industry when there is nowhere that can absorb the labor: so, subsidies. Nevermind that airline travel isn’t just for people, bt all sorts of cargo all over the world. Our “just in time” society hinges on planes up and running, so unless we want to significantly change society for good we had better bail out the industry, who has been just barely keeping its head above water money wise (after years of being in the red).
But you probably knew that too. I feel you are ready to levy a large, powerful argument on me but I am not carrying a powerful enough flash light to see it.
As far as what unions are for, raising wages should be the last thing. That’s the damn employee’s job to get his own income. Unions, IMO, should be there to protect against practices which the government would like to if they could just manage some damn efficiency, like OSHA regulations, working-day regulations, overtime pay and handling, etc. But buddy, when it comes time for review, your performance should be under evaluation, not which union pin you wear on your shirt.