Yah, people don't understand that the prices charged at the pump are more volatile with regard to the supply on hand, than the price of crude futures.
Most of the price manipulation in the past 20 years has been because the major oil producers, the exxons etc. have not invested a penny in building new refineries, thus controlling the supply. That and OPEC of course playing silly bugger with the overseas supplies. It's all part of a huge illegal anti-combine action between a dozen or so "movers and shakers" who can control the supply, and by extension the prices at will, worldwide.
As I have always said, the very thing that drives the "free market system" which is greed (or put another way, personal incentive), guarantees it's failure. You inevitably end up with the Conrad Blacks of this world trying to increase their own fortunes, by manipulating the market system to be anything but "free". The result is the little guy always gets screwed.
Sorry, soapbox time
Stan