The invisible hand working at airports

I don't mean security guards with superpowers. I mean market forces dealing with bad service. Accoding to this article in The Economist, airlines state that BAA is trying to use market forces to move people to its other airports. It certainly works for short haul flights (as you have read in my recent post I've travelled to London City), but not in the way they intend, since London City belongs to a different company!. And it is working for international flights in that weird way too: In my trip to San Francisco I used a different airpot, but it belonged to a different company. It simply will not work if you want to use London as a hub; I will never change planes by travelling from Heathrow to Gatwick or viceversa. If service doesn't improve, less passengers will fly to Heathrow, it will collect less money, and the managing company will go broke (or it will sell the rights to administer Heathrow to a different company).
It is quite funny that London City's corporate page states that London City is the only airport in London (which, according to the ASA, is true).