From my little understanding, I have been told that there are numerous tax (and other) benefits available for any company, including airlines, with regards to the training that they provide etc.. How much these reductions would affect/profit an airline is anyone's guess !?!? It also appears that airlines (particularly BA) like to be able to 'mould' cadets into exactly the type of person that would be most beneficial to the company - which is ultimately as a manager aswell as a pilot. I must admit though, I've often wondered this question too, particularly since there is supposedly large pool of un-employed pilots !?? Anyone else shed some light ???