Here's a look at net revenue per user for a basket of big internet sites from digital media analyst Ian Maude.
As you can see, it's good to be Google! It has a magic money machine called search that drums up more money per user than anyone else. That's why the next two biggest sites on the chart, Yandex and Baidu, are also search engines.
This is why Microsoft tried so hard to make Bing a dominant search engine. It's also part of the reason Facebook keeps flirting with search.
Chart via Statista.