A short addition to my post above:
Ten years ago I wrote to two leading UK airlines pointing out how many expats lived within an hour of Girona airport, and suggesting that perhaps - oh, how naive I was ! - ONE flight a WEEK back to the UK might achieve no little success. I quoted some accurate figures.....
Neither airline replied to my letter.
Today, Ryanair has fifty times that number of flights every DAY out of Girona.
Draw your own conclusions about "business models".