Well it's a version of capitalism. Left on there own without interference, markets will come up with all sorts of perverse and self destructive schemes; look at the collapse of the banking system. Not exactly a great ad for unrestrained markets.
P2F is not as great an idea for the airlines as they think it is. Not all have a job that pilots want to buy. Worst of all (for the airlines), if the aim is to get pilot income levels down, P2F schemes would not be viable as there would be fewer pilots willing to pay through the nose if peak Captain earnings were £40k