Shareholder's point is well taken; what I'm posting below is from an article I wrote about three years ago for the magazine "Mid-Atlantic Brewing News" on the improving quality of beers served at airports. Much of the information about specific places I mentioned in that article has become outdated, but I think this quote about why you're seeing better tap choices may still apply:

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...run by Maryland-based Host Marriott Services, which operates 42 craft beer concessions at U.S. airports and has more planned. “We find that if we take a generic, typical airport bar and turn it into a microbrew establishment,” explains Stan Novack, the company’s Vice President of Concept Development, “we see a minimum increase in sales of 35 percent. In some instances we’ve seen sales increase as much as 150 percent. Host Marriott likes that.”

The company likes it enough to encourage the managers at all of its more than 400 airport locations serving alcohol to make a craft beer available to customers. “We have not mandated that,” says Novack, “but it’s a strong recommendation that they try to feature at least one tap of a local product.”

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