I also pay with cash for most items. I had a debit card, but closed that checking acct. Now I would not shop there if a business wouldn't take cash.
I pay at the pump w/ a credit card and online purchases. I agree eventually cash will be a dinosaur.
Soon you won't even need a debit or credit card. You'll just have a bar code tattooed on your wrist. Now, that will sure be convenient. With the wide spread acceptance of tattoos by the masses it won't be a hard sell at all. If I walked into a retail site that didn't take cash I'd walk out with just as much as I walked in with.