Back in the 90's Mobil had a little thing you put on your keychain that did this. It was shaped like a plastic tube about the size of a match, but thicker.
I don't know what happened to it. My guess is that since most gas stations are small businesses, they didn't want to pay to upgrade all of their pumps.
I don't know what happened to it. My guess is that since most gas stations are small businesses, they didn't want to pay to upgrade all of their pumps.