>>Shops can refuse cash

>No, they cannot. Many businesses don't want to handle cash and they will make it hard and send you an invoice with a surcharge but they must accept any form of legal tender, no way around it.

Not true in the UK. The House of Commons Treasury Select Committee has been considering this issue (Apr 25): BBC News - Shops could be forced to accept cash in future,

MPs warn - BBC News https://www.bbc.co.uk/news/articles/cjwvgqz3vxzo?app-referre...