Otherwise known as the Field of Dreams marketing plan. Manchester Airport was something like that. It's a nice little airport. Ten years ago they had virtually no scheduled air service. Drove down to pick up youngest son last night. Plane was late (thunderstorms in Illinois was the excuse this time). While waiting, they had 5-6 planes an hour coming in and going out. Now they have several flights a day to NYC, Baltimore, Chicago, Washington, Philadelphia and Florida. In short Manchester now has pretty decent air service to the rest of the country. Things are so good they now call themselves "Manchester-Boston Regional Airport".
In actual fact, Manchester is as easy to get to as Logan for everyone on the north side of Boston, to say nothing of all of NH. Parking is cheap and plentiful.
You could start up a business in NH now and count on air service to get your salesmen and service techs out to customers, and get customers and vendors in to your site. Used to be a startup had to be on Rt 128 to fly out of Logan. Now a startup can be in NH, with lower taxes, and fly out of Manchester.