As for why I do this- I love my job. I like working. I have no intention of wasting days on golf courses! I am experienced and I like the mental stimulation.
Whilst this may be some sort of hobby for you, stimulation, whatever you call it, others do this to earn a living - for the money, not the love of aeroplanes.
Its punks like you that degrade our salaries. Dare I say you would even work for free if it kept you busy.
Why don't you go flying sea planes or something more exciting to curb your love for work. There is even places in B&Q for retired people who love to work!