This is a very good analogy and I accept it and agree with it completely -- until you get to the EXPORT portion. In order to export, there has to be someone on the outside to import (or visa versa) and this exchange must continue at a rate that sustains all cost to operate the system and pay all that work for it (creators, curators, etc.) in a monetary system that keeps them satisfied and fed and engaged.

For example it is unlikely there would be as many new people coming into steemit if they could never sell any of the steem they receive for anything that converts to a fiat currency or tangible assets. It would not matter how much SBD they collected if they could not purchase anything either directly or indirectly (via fiat or not) outside of steemit (Internet exchange or brick and motor).

SP and SBD and Steem only have value when they can be traded for goods that people give value to.

I do agree with you that eventually most if not all monetary transfer will be via crypo or digital means of some sort.

Thanks again for the comment.