As far as I know, a blockchain solves a very specific kind of problem you never hear people lamenting about: trust. If you can’t trust your bank or the local shop, and those two can’t trust each other, let alone you, that’s when you need a blockchain. This tool is for situations where everyone is constantly worried about someone else screwing you over and running away with your money.

If there is sufficient trust among all three parties, you don’t need a blockchain. It solves a problem you don’t have.