I guess you missed my use of quotes and use of word "theme." You are being naive if you don't think Google only has information that you gave to them. Google has an insatiable appetite to know everything about everyone because that is it's business model. For example, why do you think they are trying to install trackers on every web site you visit whether or not you are using their browser or OS? Of course, you have to use an App like Ghostery to see what Google tries to installs regardless of whether you are using a Google service. Why do you think they have spent billions researching self driving cars that they never intend to sell? It's because they intend to offer the systems that record where each of us drives, what is said along the way, where you stop, and to offer ads along the way.
As far as financial data, Google has tons of it on you. If it is ever mentioned in any email you've ever been sent or received. If there's any financial data on anything you upload. They also know what you are buying, where you drive, where you stay, where you live, house information, where you work, your occupation, your family information, your marital status, sexual orientation, etc. Why do you think they are amassing this data and linking it all together? 90% of their revenue comes from selling access to you. When your partner sends you an email with a link to a potential vacation spot, Google has that info (if you are using Gmail), but they make more money by linking it to your income and where you live so an advertiser knows whether to send you an ad for an expensive cruise to that area or a budget travel package and which airlines serve that area. As Google learns and stores every fact about you, that linked information becomes only more valuable.
Why is it so difficult to accept that Google has an entirely different business model than Apple and is incentivized to collect and store every possible thing about you, but Apple isn't? To accept that Google couldn't give everything away for free if they didn't get something in return for your data? Facebook is similarly entirely dependent on selling to advertisers to stay in business. That's why you saw a leaked report where Facebook had demonstrated that it could provide a target "audience" of teens experiencing emotional crisis to advertisers from the information it was collecting on Facebook users.
Well if I'm going to have advertising put in front of me, I'd rather it be something I'm interested in. Using business intelligence to improve advertising is not evil. I fully understand Google's business model. I've earned over six figures from Google ads and also used them for targeted advertising.
Evil would be if they were using the data they collect to hack into my system and rob me. My data is probably safer with Google than it is on my laptop or phone. As you said, the data is worth a great deal to them and if they ever were caught using it for something evil, it would do significant damage to their business. They make plenty of money on advertising so they don't have any reason to resort to evil things.
Where we differ is that I know most companies are collecting and using data for business intelligence, including Apple. Heck, this past week Amazon showed me pool skimmer baskets when I hit their page. My skimmer basket broke the week before and I swear I can not figure out how they knew. I don't recall doing any research online on the subject. Maybe google has a satellite feed watching my house and saw me break it. Maybe they are bugging my house and heard me tell my wife it broke. I don't really care.
As for Facebook targeting teens freaking out. Based on my experience on Facebook they'd not have a hard time finding them. And there is nothing wrong with them mining the data on their servers for advertising. That is why the system is free.