I wonder about that. Amazon is basically Walmart without the profit. Even the most staunch defenders of Amazon's business model can't get around the math that Amazon's only hope for profit is volume, and the only way to make volume is to eliminate profit.

They are a cash poor organization. Rather than link to Business Insider, here's a fun quote from January:

We just explained why the market currently loves Amazon and hates Apple. One of the reasons this drives Apple lovers crazy is that Apple's profits are significantly bigger than Amazon's.

"Significantly" might not be a strong enough word for the difference between the two companies' profits.

Bloomberg editor Mark Gimen points out that Apple earned $13.1 billion in profits last quarter. From the time Amazon turned a profit in 2003 to the end of 2011, Amazon has earned $5.1 billion in profits. (From inception, adding up losses, it's $1.5 billion, says analyst Benedict Evans.)

We want to say that again: Amazon's total profits are ~$5.1 billion. Apple did more than double that in the last three months.

(Amazon's price-earnings ratio is currently a mind-boggling 3,275x. Apple's is 10x. Traditional valuation metrics are obviously pointless for Amazon, but if you were to use Amazon's PE for Apple, the stock would be trading at $144,618 per share, for a market cap of $136 trillion. Those numbers are totally meaningless, but it's funny to think about.)