I agree with some of the problem with the LCCs cherry picking their cities, but I don't think that is the only proble.
Because of my job, I always fly one last minute one-way fares. Part of the problem I see with some of these airports is the highway system has improved, and the hub and spoke model has made it easier to go to a closer larger airport.
Some of my other examples is Youngstown, OH; I can (in the past) fly to PIT, rent a car and be in Youngstown sooner,rather than wait for a connecting flight. Maybe that is one reason Youngstown is no longer served.
Other examples are Latrobe PA; from PIT
Hagerstown MD from DCA, BWI, IAD
LAN, from DTW
Rochester, MN from MSP
And my list could go on and on. It is not just a US problem, it is a problem with many carriers, and sometimes to get where you need to go from these smaller cities it is a double connect so all the more reason to take the hour to 90 min drive.
Fares are not always the problem either. In the winter I ofter fly inot LEB rather than my home airport MHT. I do this when the schedule works for me as well as the fare. Many times it is alot cheaper to fly to LEB rather than MHT. And I know they must be loosing money since the plan (B1900) has few passengers. It would not surprise me to see LEB go away. I thinf Dartmouth College must be part of the reason the airport is still open. There is also very good public transportation from Lebanon, NH to MHT.
It will be only a matter of time that you will not see service from many smaller airports.
I travel usually from MHT west to ORD, South to CLT and some FL cities. And my average one-way ticket this year is $560.00. On US the average is $445.00, so I have seen some price drops. NW has the highest average with me and that is at $605.00 for one-way. In agreeing with ARTfrom ISP, the top fares need to come down some, and the bottom fares up some. People like me are tired of subsidizing people flying from small airports that don't make money, and people who fly transcon for $200.00. If these smaller airports (non-subsidized) charged what it actually cost to operate many of these flights, people would have left them long ago. You just cannot support a station on 120 pass. per day, on short flights and make money.
I soory for the people who must drive to PHL from Reading to fly somwwhere, but that is all part of deregulation, and letting the market forces decide what are the profitable cities to fly to/from.