An airport tower controller doesn't want you calling if you're not taking off, landing, or passing through their airspace.
And the TRACON (Terminal Radar Approach Control) doesn't want you contacting them in such a situation as they have enough on their plate.
Actually, come to think of it, he does cross the landing path when the planes come right over the city coming in out of the NW. They fly right over the city on their approach to the airport. So, he must have to call in to make sure there is no traffic in the flight path.