You just answered your own question. Our actions do not affect the market, theirs can due to extreme leveraging. Also cornering markets, you must have heard about the drug scandal, how much did the price go up of the patented drug?
You realize that's a good thing right? Capitalism works over the long haul, through bubbles and busts, despite all its inefficiencies. If your observation was correct then the myriad of price controls in Venezuela should have catapulted the country into an era of fantastic wealth over the last 10 years. Instead, they're bankrupt.
