We can't deny there's tax evasion due to cash, but the failure...

We can't deny there's tax evasion due to cash, but the failure ("outage") of bank technology a few months ago showed the importance of retaining cash. Thousands of businesses lost money that day because shoppers/customers could not pay, so sales were not made.

It's extremely useful for the large number of disabled persons and others who lacking a smartphone and not be conversant with modern technology.

Internet access can be problematical or non existent in some Oz rural areas: cash obviates that problem.

I dispute it's much slower for shoppers: provided they have the money in their hand and don't fumble around in a purse or through a wallet, the time difference is negligible.

A high percentage of WOW and COL shoppers use self-service machines of which typically now, two or three in every store might accept cash. The rest are credit/debit cards only, even in larger format stores that are WOW supermarkets, not smaller Metro stores.