"To correct another kneejerk comment far above about Exxon-Mobil, the prices of crude are set by demand and the Commodities Market."
The problem is that big global companies like Exxon are both the producer and the purchaser and the wholesaler and the seller of the product. In other words they are pumping the crude and then charging the refiner wharever they wish for it. The refiner then sells gas diesel etc. to the distributer/wholesaler who then sells to the retailer. This becomes a problem when they are all one and the same. The law of supply and demand fails and corporate greed rules supreme.