IMHO...
Cryptocurrency and blockchain technologies play an essential role in deep space commerce. This assertion is based on 4 truths:
The fourth industrial revolution will establish an in-space (or deep space) economic infrastructure that is self-sufficient and profitable.
Sending paper money from Earth to space, for use in the deep space economy, will never happen.
Conducting financial transactions for deep space commerce using Earth-based financial institutions would be inefficient.
Finally, using in situ resource utilization (ISRU) to create physical currency for use in the deep space economy will never happen.
Therefore, cryptocurrency plays an essential role in the establishment of the deep space economic infrastructure. In order for the human presence in space to grow at a significant enough rate to establish a true self-sustaining, profitable economy certain technologic developments are required. These include operations being conducted by companies like SpaceX, Deep Space Industries, and many more. My argument is essentially that these businesses and the people they employ in space will eventually use cryptos in day to day life for all deep space financial transactions.
For example, the systems like Power Ledger would be used all over in a Martian city. Iota and Hdac could enable deep space mining industries to operate private ledgers that track ore from the mine to the customer. Different players in the field have different business models and would use the technology to varying degrees. People would also use a high speed, full scale cryptocurrency for day to day transactions. What other uses can you think of?