You can disable them from the Options->Add-ons menu but, as explained so many times on the forum, while this might be necessary for any other scenery out there, FSDT/Flightbeam airports, which used the Addon Manager, do their own memory management, which means every objects that is being created *only* when you are approaching the airport, usual about 15 NM out, will be destroyed and the memory reclaimed, as soon as you exit from that area so, disabling them "to save VAS", is just a wast of your time and effort.