I think alot of the price fixing is done at the local level. How often do we see stations next to each other match prices within a day of each other. There is a small local station that increased their regular gas to $4.14, then within a few days, went to $3.92 and they have a line of cars now!!! I think they found customers weren't stopping in anymore...
You could be correct. I see the same kind of thing here in Kentucky; it's like they all pass around a 'memo' that says "on Tuesday, everyone raise the price $0.10/gallon," and lo and behold, that's what happens. Now I
know they all didn't get a shipment of fuel on Tuesday ... but they all change their prices on Tuesday...
They're also fond of what I refer to as the "yo-yo" price game here in Lexington. Almost without fail, the price spikes up on the appointed day (by as much as $0.15-0.20/gallon), then hangs there for a few days before slowly creeping back down to the "outrageously inflated" level that's the "going rate." If you're running on fumes on the appointed day (or a few days afterwards), you're just SOL... Fortunately, they're also creatures of habit here in Kentucky, so it didn't take me too long to figure out the rhythm of their price "yo-yo," and adjust my refueling habits accordingly...
But realistically, I just think most people don't even pay attention to local variations; they just buy fuel wherever they are, whenever the needle points to "E." There are three Shell stations, all within a 3-mile radius of one another here in Lexington; they all have subtle variations in the "yo-yo" rhythm I described, but I frequent the station that consistently averages the lowest price. Oddly enough, the other two stations don't seem to hurt for business, though...
... The gas tax is .43 in Maine and I'll bet they'll find a way to increase that. I wish ALL gas pumps showed how much the state is getting in taxes for each gallon!
It may vary from state to state, but I know I've seen a placard on the pumps here in Kentucky itemizing the additional fuel taxes. Seems to me I've seen those kinds of placards elsewhere too.