I'm not sure you can look at Stobart in this way. Sure they lost a load of money on their flying but to me, there was clearly an ulterior motive.
They own the airport and so launching flights was an investment to prove that a market exists to attract the likes of Ryanair and probably others. This will significantly increase the revenue at the airport (all of which flows to Stobart) and at the same time increases the value of the airport itself. In a few years time the 38m 'investment' could produce them a very healthy return.