[user104658]

I guess part of the concern is, if the systems go down say for a couple of days, people wouldn't even be able to get food. I mean I'm in a little village with at least one shop that would probably "open a tab" for locals but I don't imagine most places have that.

That said - I pretty much never carry cash... Always a pain in the arse when kids need coins for bake sales and stuff like that, because I have to go to the shop on the way to school, get £10 at the cashline and then buy something to break it. I should just keep a stash of coins in the house...

In general though I don't see a problem with it, cash has no more inherent meaning than digital funds when it comes right down to it. The psychology of money is quite interesting really... It's only worth something because everyone agrees that it's worth something.