The Oil Drum: The EROI on supplying fuel

You are a farmer in the less populated parts of the country, and you drive over to your local gas station, after noticing that you have less than three gallons of gas in your tank. You get there to find that the station has closed, and there is a note on the door that says that the nearest station is now 50 miles away. If you can make it to the station, and if your car gets 20 miles per gallon, you will now use a third of your tank of gas, each time you fill up, just in filling up your 15-gallon tank. (Until you also start filling gas cans). What then?
The Oil Drum