"'But when they retire, they can always work in call centres, I suppose."
I know lots of pilots, I know quite a few Ops Officers. This is what they are now doing since they 'retired':
Ex Ops O - Lawyer, £100,000 pa plus
Ex Ops O - Doctor, Consultant within 7 years, £90,000 plus (massive overtime too)
Ex Ops O - Software Sales, £100,000-200,000pa, very social hours
Ex RAF Pilot - Airline Pilot, £40,000-75,000 pa plus shift work for the rest of your life!