I guess that would depend on weather one could find an individual willing to sit on the wing with a bag of seed, pitching handfulls out in an orderly fashion ;o)
Seriously, aeriel seeding was utilized in the 1960's with sporadic success. Main problem was uneven application...some areas got no seed, other areas came back like dog-hair. As far as cost, I don't know anyone who does it. The closest thing would be helicopter application of granular herbicide I'm guessing $170 - $210 per acre.
Mighty telling, isn't it, that a federal bureaucracy has an association dedicated to saying what they couldn't say when they were employed?