I can't see where the article's scary headline is justified. It appears that all that happened is, he used this service without knowing it was based on tracking app usage, and was surprised when he found out.
Agreed, but it is pretty surprising, and most people will have no idea this is what's going on. I couldn't find it mentioned on the Amazon Underground homepage:
https://www.amazon.com/gp/feature.html?ie=UTF8&docId=1003016...