Possibly worth observing: they bring in a ton of gross cash, but their revenue is smaller than a lot of Internet operations because their out-lay is high: physical storage, transportation, etc. are all expenses that Internet companies with similar profits don't have to shoulder.

In 2016, they made a profit of $857 million on a revenue of $30.1 billion--- i.e. profit margin of 2%, compared to Alphabet's 9.7% or Facebook's 36%(!!!). It's the number that investors care about, because it tells them how likely they are to get money back out of a business when the invest money into it. It's also a number the company cares about, because it tells them how much of a shock to their fixed costs they could stomach without suddenly finding themselves spending more than they make to keep the doors open.

Amazon's (relatively) razor-thin margins are what make the company so paranoid about costs like wages and benefits; they've seen America's history of burning hulks of older companies wrecked by making pension promises when profits were high that they couldn't honor when profits tailed off.