I was an early adopter of (debit) card only, using it for everything in 1999. Your experience has never happened to me, as far as I recall. I don’t think I’ve ever had to go to an atm because the reader didn’t work.
The main reason I carry multiple cards, and Cash was because my debit card was used for fraud once, which shut down my card, and it took several days to get a new one.
Now days they can print you a new card in real time at the branch, but still I will never not have cash, and not have a backup card
I also NEVER use by debit card for anything other than ATM now, credit cards and pay it off every month... I dont even carry my debit card anymore, it is locked in the safe, and a bring it out when I need to get more cash.
Well, it happened to me just the other day - said it cannot read the card or something like that (even though I had used it less than 15 minutes earlier in another shop). There was already a queue behind me so I forked $40 for gas and went on my way.