Quick and short. working day.
FEMA should requisition the field fuel trucks from the Army and sweep through neighbourhoods pumping 10 gallons of gas to every car/truck that wants it.
Just maintain a data base of the license plates. Let the people know they will get
a bill for the fuel later. With some simple central data base to stop a few people from
hogging the supply. Cars can be tracked and the money can be collected later.
Later FEMA can price the fuel as the average price of gas in the unaffected
parts of the country. And sell the entire money to be collected to some
private company at 95 cents to a dollar or so.
There will be some loss, and the cost of filling fuel at everydrive way would be
more than selling it in a gas station. But this is an emergency.