In my area, gas prices are based on ability to pay. In poorer areas, like mine, gas is always the cheapest, $1.87 today. In more affluent areas, it's more expensive, like $195, or a bit more.
Tip: Buy gas in poorer areas!
They all do. But we haven't built a new refinery in this country since 1968, and we've torn down a bunch, because they're icky, they stink, and they're ugly, so no one wants one in his back yard...but everyone still expects cheap gasoline as some sort of birthright.
California is the worst of the bunch in this regard. We don't want to build more nuclear power plants (because they have the word "nuclear" in the name), they don't want to build more oil or coal-fired plants (because they put out icky stuff), they don't want any more hydroelectric dams built (because they make rivers less wild and scenic), and they don't want any more windmills built (because they're "condor cuisinarts")...but they still expect the damn light switch to work, and the bill to be nice and inexpensive.
Refinery capacity growth hasn't kept up with demand growth. So where we used to have a buyer's market, we now have a seller's market--and the buyers are (a) unwilling to make the changes necessary to make it a buyer's market and (b) resent the sellers.
At some point, Californication is going to outlaw "profit" because only "greedy people demand profits."
It would seem advantageous to some companies to have their own refineries, so they can capitalize on sporatic short supplies.
Yeah, well, try actually BUILDING a refinery in this country. No one will let you. EVERYONE will tell you to build it somewhere else. Everyone wants gasoline; no one wants the production facility in their neck of the woods.