Having to make sure you have enough cash with you, counting it out carefully, making sure you get the right change in return is part of the ceremony of cash. You are physically handing over some hard earned dosh and reminded of how long it took you to earn it.

Whereas if it takes place in a virtual world where cash flows in and out of your account there is no moral checkpoint at the point of purchase - do I really need this? Everything becomes simply a matter of cash flow, and provided you aren't going heavily into arrears there is no problem. No putting aside a few notes in a mattress for a rainy day.

And besides, the taxman gets to see everything.

Cash also feeds into the conservative myth that money is a real thing, in and of itself, and not merely an arbitrary unit of exchange. Having a big wad of it defines who you are, makes back-handers easier, and assists in the negotiation process. (Don't show them your €50 notes if you only want to spend €20!).

Protestant thrift means putting  your €50 note on the collection plate where everyone can see it. Otherwise, what's the point?

Index of Frank's Diaries