Maggott17 - you are kidding right...
You could even sell the Towers and Approach to the airports and just leave OZZIEATC as an enroute organisation.
Clearly you haven't worked TWR or APP. Do you really think they only provide services to the primary facility?
What about the surrounding airspace? Transit flights, airworkers, IAL into other proximity airports, sporting aviation, etc.
Do you think an airport owner would be happy paying expenses for services that don't benefit their investment.