This is fun, but Amazon and Walmart's revenue are sort of misleading, since they obviously don't get to keep most of it.
I made $700k on the deal, not bad. I moved more than half a billion. The _revenue_ number is huge but mostly irrelevant from my personal perspective. Almost all of it was money that was never mine, that I never made.
In the case of companies, it can also show how much of the market a company has captured (when revenue == sales).