The other reasons is that cash always works. I once found out during checkout in the supermarket that my card was blocked by my bank (probably because I once us

The other reasons is that cash always works. I once found out during checkout in the supermarket that my card was blocked by my bank (probably because I once used an ATM which was hacked). It's not fun to stand around blocking the whole checkout process because you can't pay. Since that day I'm always keeping enough cash in my wallet to be able to pay without any cards.