I was a bit leery on using your phone to pay, but NFC and Android Pay saved my ass when I was below zero on gas and realized I forgot my wallet. Having set my account up a week or two beforehand saved me from having to push.

At the same time having physical cash on hand was stressed by my parents, and using electronic payment isn't always an option. If I have a taste for 5 wings and fries the carryout may not have a card reader, so...