It's greed and stupidity combined. In most cases people don't have the ability to calculate what risks are tied to whatever investment. Gambling is what I consider a poor mans way of becoming rich, but that's also the case when it comes to all kinds of worthless scam sites that promise you insane rewards when you hand them over your coins. No matter how many times people are told to avoid certain sites and services, there still there are enough people that fall for it. They try to achieve something that in normal circumstances isn't possible with their level of wealth. That's why a lot people keep falling for scam sites, keep losing their money with gambling, etc.