Doug, you seem to assume that making money = prices going up. The equation is not that simple -- if prices drop by 10%, and you pass 9% of that cost on to your consumer, your profit margin still goes up. Then there's commodities trading (too scary for my wallet), where you can profit by correctly predicting prices go down. Then there's little issues like Bush the Lesser selling off a passel of oil stocks days before Bush the Elder attacked Iraq the first time.

The money is really in being able to manipulate the market, not just driving prices up.