I'm not a microlight pilot, but....
1) A microlight licence is cheaper to get.
2) Microlights are cheaper to buy, on the whole anyway.
3) Microlights are much, much cheaper to run.
4) In my albeit limited experience (a trial lesson on a Thruster, and up to first solo on a flexwing) microlight schools are pretty friendly places.
5) You don't need to spend so much, and jump through so many hoops, to get a medical for flying microlights.
6) Microlight schools/clubs are a trifle anoraky, but no-one seems to mind a bit.
So, since shortage of money seems to be a large part of the reason why people give up, why aren't they being directed to a form of flying that they can afford?