On a related note, here's a story that the attorney general in Florida has received 1500 complaints about gas price gouging due to Hurricane Ike.
What happened was that when Ike was heading into Texas, the word was that the refineries would be shut down to the Southeastern U.S. There were concerns about shortages and a number of stations in Orlando (can't speak to other areas of the state) raised prices a dollar or more overnight up close to $5 a gallon to take advantage of people gasing up in advance.
So don't think it can't happen.
Officials receive 1,500 complaints of gas gouging -- OrlandoSentinel.com