Wizz.....
Just to try to put this to bed, Curious Pax has it spot on.
Airports and Airlines don't exist in silos, they will be constantly talking to each other.
My background is Banking, but it's no different from a business perspective. We expect to gain business off the competition. We maintain lists of companies who bank with the competition - Barclays, HSBC, Lloyds etc - and we build relationships with them. Some have fabulous relationships with their existing bankers and will never move. Some are always looking for the best (cheapest) deal and will move at the drop of a hat. The majority are somewhere in the middle and it will often take some kind of event (eg a mistake) to prompt them to talk about moving. The key is relationship building and being able to demonstrate value and trust - old fashioned values which still hold true.