It only shows you what you give it. The only thing Amazon sends me offers about are computer peripherals because that's all I've bought through them. And Facebook only shows me travel ads because I only post details about my vacations on there. And Google only shows me ads for web hosting because most of my email is about website development.

None of these services know that I'm into hobby bonsai because I've never given them that information. So if don't want to be followed and frightened by them, then limit how you use them.