A report from an executive of DuckDuckGo attending the antitrust lawsuit against Google:
"Google likely alters queries billions of times a day in trillions of different variations. Here’s how it works. Say you search for “children’s clothing.” Google converts it, without your knowledge, to a search for “NIKOLAI-brand kidswear,” making a behind-the-scenes substitution of your actual query with a different query that just happens to generate more money for the company, and will generate results you weren’t searching for at all. It’s not possible for you to opt out of the substitution. If you don’t get the results you want, and you try to refine your query, you are wasting your time. This is a twisted shopping mall you can’t escape.
Why would Google want to do this? First, the generated results to the latter query are more likely to be shopping-oriented, triggering your subsequent behavior much like the candy display at a grocery store’s checkout. Second, that latter query will automatically generate the keyword ads placed on the search engine results page by stores like TJ Maxx, which pay Google every time you click on them. In short, it's a guaranteed way to line Google’s pockets."
I hope we'll see more evidence proving or disproving this, since September 28, the court established a process allowing the Justice Department to publish more information about this case.
https://www.wired.com/story/google-antitrust-lawsuit-search-results/