Self-paying loans and the magic of Alchemix
threebody.capitalSummary for those with better things to do than read this:
If your cryptocurrency scheme pays more than a loan does, then you could have "free" loans by funding them with your cryptocurrency scheme.
Of course, if your cryptocurrency scheme pays a lot one could just get rich from the cryptocurrency scheme. Everything else just consists of pretending that risks don't exist.
This is standard leverage: Borrow money at rate x to invest in something that has a return >x. Nothing new, happens all the time.
Of course, as you mention, the key is the element of risk. If you borrow money to essentially gamble you could get rich, but you could also go bankrupt.