Let's be honest - the reason why people are willing to put blind faith in these operators boils down to greed.  They're "investing" on the slight possibility that the scheme is both legitimate and sustainable.  Intellectually they might know that there's a high risk of failure, but the remote possibility of easy money hooks them emotionally - especially if they're people who unlikely to ever acquire wealth by conventional means. 

What is utterly ridiculous is that people keep investing more than they can afford to lose in these ventures.  Every time a Bitcoin venture fails we get posts about people having lost funds they needed for day to day expenses, or even worse, losing funds they'd borrowed and now can't return.  If you wouldn't bet the amount you're placing in Bitcoin schemes at the casino, then you need to consider how catastrophic the failure of your investment would be to your real life.