Good point!
Going back to my example, that 40 hours in a C150 probably used about 1000 litres of AVGAS. Fuel duty is 40p/L, so that's about £400 in fuel duty.
The rest of the £4.4k, so £4k, probably all attracted VAT, so that's about £660.
Interesting, so the basic cost of a PPLing habit is about the same as a cocaine habit. The difference being that a PPL pays an extra £1,060 in tax which the cocaine user doesn't.
Good for society, but not a great advert for flying as a hobby in itself !
G