My pickup, hauling a tall cabover camper, ran out of gas on I80 in Iowa one summer about 20 years ago. We were heading into a 50 mph wind, and the last thing on my mind was needing fuel so early. I hadn't been paying any attention to the gauge. I think it's the only time in my life that I ran out of fuel.
I went back to the camper and dug out a 10-year-old can of Coleman Fuel and dumped it into the tank. Truck started right up and headed to the next service station, a couple miles up the road. :) Works in an emergency.
I always buy Coleman Fuel for my old Coleman stove and lantern -- always as in every 5-10 years! :) At most it might cost me 50 cents per camping weekend. I think it's closer to a quarter. I can afford either one.