HSV (Huntsville) is just 15 minutes away but it is also usually in the top 5 most expensive U.S. airports to fly from. Flying to Miami round trip is usually close to $400 per person these days. Just a few years ago it was more like $150, but then all the mergers started happening, schedules were reduced, and RJs (regional jets) became the usual airplanes flying to and from HSV which means fewer seats to be had. It used to be that about half the flights were in DC-9 sized airplanes but now the 50 seat RJ is the norm. When NW and Delta merged it really hit us hard.
So - the price of convenience for us is to either suck it up and pay the HSV price or drive to BHM or BNA. The convenience is still winning out so we pay the premium and fly from HSV. I prefer a quick ride home to a 90 minute drive on an interstate.