The simple fact is, you can never trust they're not doing it, no matter what it seems like or what they say. This kind of technology needs to be kept out of public places, open hardware, open source and self-hosted, without exception, otherwise it is creepy.
I'm not saying whether or not that's a good decision, but saying "you can't" is misleading. Trust is a choice, and time tells whether you made the right one.
