Bill,
In my 46 years of driving I did forget my wallet once. I was working on the car and had changed pants. Decided to go fill the gas tank, gas was around a dollar a gallon then, and when I started to pay I had left the wallet in my other pants. The station was about 1 mile from my house and one that I used often. They were so trustful they demanded that I leave 4 kinds of identification and I think the gas bill was about $9 dollars. I had my check book only and they wouldn't take a check. So then they wanted me to leave the car keys while I went home to get my wallet. I asked them which one was going to drive me home and then it sunk in that if I left them the keys I couldn't drive the car. I never told them I had an extra set with me at all times. Moral of story, is that it is possible to leave your wallet behind.
Ron