People's humanity.
If I could run away with lots of money and don't take any risk, then why not?
It's just a nature of human.
But why would you do it if you have a chance at making more money in the long term? That is the only bit I don't really understand about some people...
Greed. At some point they've got to run or people may stop investing or sending them money, but I agree it is better to build up a profitable and legit business.