A good point and well made, however in the very competitive London airport environment, I wonder how it makes sense. LTN, STN, SEN compete on price with low airport fees with the cost of trolleys and clear bags for security met by the customer. LHR and LGW offset this partly by having a massive retail income, and LHR will be charging for new facilities at T5 and T2. LHR is also a magnet for world airlines.
LGW is still easyJet, Thomson, Thomas Cook, Monarch and fly be dominated. Even the BA fleet is leisure focussed and very price competitve against EZY, so I doubt LGW can hike prices up too high. The competition on price is too heavy.
Nothing wrong with excellent facilites so long as they're commercially viable, the new Stansted terminal never actually was though it's really nice to use. It exists as a cross subsidy from LHR via BAA.