You intentionally miss the point that a whole load of long haul routes are successful only because of the feed?
Indeed. One of the greatest economic developers and supporters you can have is an international aviation hub. Dubai became not only an airport with people connecting but also the main economic centre of The Gulf, despite having hardly any oil. If it wasn't for connecting passengers Dubai would still be back with a few buildings around The Creek and a scatter of flights. Frankfurt managed to develop as the German financial centre and international business location, despite having by no means the largest population or economic base. It was a pretty small place 30 years ago.