Thing is it's so obviously the Salt Lake City airport. The Denver airport is very distinctive as well, which means that even if people don't know SLC they will know this airport is not Denver if they see it. And if you know that Everwood, though set in Colorado, is actually filmed in Utah, you know why they used SLC.
It reminds me of "The Peacemaker" when they're running through an "airport" and it's the Jacob Javits Convention Center. Or the second "Die Hard" movie when they're supposed to be at Dulles and there's a Pac Bell phone.