I don't think this is a fair comparison. While Google does make most of their money from ads that result in a purchase, that purchase is not always the sort of

I don't think this is a fair comparison. While Google does make most of their money from ads that result in a purchase, that purchase is not always the sort of thing Amazon sells. For instance one of the highest grossing per-click terms has consistently been mesothelioma. I'm guessing Amazon won't be selling legal services this year. My suspicion is that much more of Google's revenue comes from purchased services (and I'm counting their #1 spender, eBay, as a service), digital or otherwise, than tangible, shippable, durable goods.