I think that one major problem with both cryptocurrencies in general and steemit in specific is that market prices are too easily manipulated.
I think you will find that if you dig down into the upvotes for the movie review, you will find that most of the money that the post generated came from a bot farm of steemit accounts created and loaded up with a huge amount of SP specifically for the purpose of generating a lot of rshares for mediocre posts.
Thanks @sc0ut for the good insight :)