There's an argument that Bezos is forgoing short-term profits by re-investing those into growing the business (expanding into AWS, marketplaces, Zappos, Kindle, streaming media, etc, etc) and into aggressively competing on price to not leave much excess oxygen in the room for competitors.
That's very different from the potential profit profile if Amazon were seeking to maximize near-term profit as opposed to maximizing near-term growth, with the expectation that that maximizes long-term profit.
That's very different from the potential profit profile if Amazon were seeking to maximize near-term profit as opposed to maximizing near-term growth, with the expectation that that maximizes long-term profit.