What if I don't want a train ticket? What if I want to sell my widget-coin for some brussel-sprouts-coin. Now I can't go to any farmer because he's only got carrot-coin or broccoli-coin, I have to find the brussel sprouts farmer-and not only that, but the brussel sprouts farmer who wants to buy widgets.
And if you say "nonsense, you can exchange any coin for any other coin", how is that different from what we have now?
The MetaCurrency Projects’ Holochain is the next generation P2P no-middle-man accounting system which open sources and decentralizes the rules around money creation and usage. It allows us to evolve the rules together and build mutual credit, interoperable, open and unencloseable carrier’ currencies. Currencies are backed by real world commodities, leading to a rich network of flows between a community.
Your comparison shows me that you might not yet have had the privilege of critically exploring the underlying patterns and stories that have made Industrial Age money the tool it is today. For me ‘The Future of Money’ by Bernard Lietaer, and David Graeber’s ‘Debt: The First 5000 Years’ are very paradigm shifting books and helped me to challenge the underlying stories of economics that I believed. These stories stopped me from seeing a more beautiful future.