It's hardly a banal point for certain uses of cash. It doesn't matter for me buying a 6-pack of beer at the corner store. But if, say, one of your employees has walked off with the day's cash, the reversibility of the transaction becomes extremely important to you.

Given that the relative advantage of cryptocurrencies is strongest for a variety of financial crime, I think the distinction matters even more. As the Bitfinex thieves are learning, cryptocurrency transactions are not as final as they would like.