You not caring about what they do with your data is totally fine but in my opinion you should care that they (in this case Google) have not only yours but everyone’s data. It’s astonishing what you can do with just some metadata. You can influence groups of people like never before. Swing Elections & change governments. Influence public opinion about literally everything to no small degree.
You’re not just giving them your uninteresting data you’re also giving them an enormous amount of power.