Running your own wallet and such is simply beyond what most people are capable of. Hence they outsource it to an exchange. But the main motivation for people b

Running your own wallet and such is simply beyond what most people are capable of. Hence they outsource it to an exchange. But the main motivation for people buying into these coins is to speculate on them, having watched the bitcoin billionaires bloom. And while I think there's a strong argument that "they should have known these crazy returns were too good to be true" I also think you have to take seriously just how hugely this stuff has been pushed in media, and by huge traditional financial player as well. When all the apparent authorities are saying "this is awesome join us" it's just inevitable that a broad swath of people will take that at face value.