The answer is simple - DON'T DO IT. Just steer clear of these schemes in the first place. If you ALL STOOD TOGETHER and refused to take part in what possibly is the worst thing to happen in the field of aviation employment then it will stop.
Its never going to happen though because some idiots will still do it just to get ahead in the queue for a job. There is no Pilot unity.........and there aren't that many Pilot jobs for the newly qualified ones to go to. In other words you are "two a penny" and you have made a bad career choice!
Pilots will fly for nothing, or fly for food. I don't see Train Drivers or Plumbers working for nothing!
Good luck - get out and put the experience behind you.