@Bluenose re: except
"Have you tried to buy an airline ticket, car, theatre or concert tickets or any one of a host of other items with cash. Probably not because you would realise that its rarely possible to do it."
Airline ticket: yes, tried and succeeded several times (but usually use a card)
Car: yes, tried and succeeded several times (but more often write cheque; used card just once)
concert tickets:yes, cash works fine for more than 50% of the concerts I go to
theatre tickets: yes, cash works fine for more than 50% of my theatre visits.
host of other items: well, I don't buy my fixed line phone service, my internet access, my electricity, my domestic gas, my life assurance, my tv license, my water rates, or my council rates with cash - direct debit is much more convenient; but cards are pretty useless for any of those. And I don't do internet shopping with cash (it would be difficult), and tend to do car insurance, car tax, tv licence with cards. When I was paying into a private pension fund, I did that by direct debit for regular payments and used a card only for one-off payments. Tube tickets - used a card for Oyster automatic topup; train tickets - cash or card depending on how much.
Apart from internet shopping, my main uses of card are paying for restaurant, meals, restocking the booze cupboard, and supermarket shopping if I'm buying a lot, and car hire when not in the UK (where my car lives).
"rarely possible"??? Rubbish, all the things you named can easily be bought with cash.