First of all I want to congratulate you. They picked your presentation! And as you said, it is an amazing opportunity to sell cryptocurrency to Martian Society.
I know, that at this point it is pure fiction and we won't have anything like 'martian economy' to worry about during our life time.

But honestly now that you bring that topic up I don't think that anything beside cryptocurrency is good enough to power future martian economic ecosystem.
What is the key here is block chain which is trustless system which eliminates every potential 3rd party from the picture.
Also the fact that cryptocurrencies can't be counterfeited in any way (if the system is backed by enough hash power and it is solid, that is).