lovejet ... I think you will find that the argument is flawed!
Airlines want to maximise money, even the low fare ones - that's why they employ canny yield managers to maximise revenue - if they were so insistent on offering the lowest fares - they would offer the £0.99 fares during the biggest football matches to make it cheap for those fans to get there.
The fact is, airports do not shift the blame, they are the poor relation. Airports have massive fixed costs, as I am sure you are more than well aware, yet have very limited means of recovering that cost. The argument that the airport can get all its revenue from the passenger is just pants. To cover the costs of running the airport, EVERY SINGLE passenger who walks through the door would need to be spending between £40 and £60 in the terminal - why? Because the airport only gets a concession fee (a percentage of what the pax spends) and the concessionaire has to cover their own costs, make a return and then pay the airport - can you say hand on heart you spend £40 in the airport EVERY SINGLE TIME to make a trip? - Even those bsuiness passengers who the airlines love but turn up with 30 mins to spare, check in buy a paper and jump on the plane?
The reality is, airlines continually report record profits growing year on year, and the airports from which they fly report heavier and heavier losses - government imposes stricter security regimes the airlines wont pay as you have said yourself - they wont absorb the cost - who pays? The airport. There is in my view, an inbalance between the airport and airline relationship in some cases.