I've often wondered if something like this might be going on - if I wanted to make spyware, I imagine an adblocker or other privacy protection extension would be an ideal way to do it. General rule: if a company buys an extension, they're up to no good, as there's no money to be made from doing so.

(iOS is probably a tiny sliver of the 11 million, given the complexity of installing non-App Store apps)