Two French ideas are worth copying.
One is that cash is categorised as legal tender, and payment in readies cannot be refused: no signs in shops saying, ‘card payment only’. The abolition of cash not only means the banks control our lives (and can therefore ‘de-bank’ us if they choose, as in the Nigel Farage case).
The disappearance of cash is also unfair to the poor, to charities and to those whose livelihood is helped by tips, and by grandparents who enjoy