The free fees for Helicopters thing is a move by Weston Aviation & not the airport. It should also be noted that Weston are probably the best performing company on the airfield at the moment.
It's probably also related to the fact they've also just rented an office in their building to a company called "HeliNorth" I believe. Not sure what their speciality is (training, charter etc?) but it can only be a good thing?