"One big question is why a crypto-based rewards system has any relationship to other currencies."
Since Bitcoin, cryptocurrencies are all about emitting money through a reward system. One day we will look back and wonder how we had let central banks emit money without work. (I developped this aspect in this article : https://steemit.com/steemit/@jako/why-the-concept-behind-steem-is-far-more-interesting-than-the-one-behind-bitcoin)