1) I don't agree with this. If I walk into (or around) a Best Buy and they capture my movement on a security camera, are they stealing from me? Technically, they are recording data of my movement. Also, stealing generally infers that the victim is left without the stolen item. That's why we don't call piracy stealing. So, if anything, trackers are 'pirating' my browsing information and possibly reselling it. Truthfully, I wasn't doing anything with that information before, so my life hasn't changed for better or worse because of this. No proof of bad thing here.
2) It is a useful standard. I avoid being nit-picky about the little things, and so I like to make a distinction between things that are worth worrying about. If ~$273 is taken from my bank account over my entire lifetime (based on average lifetime), I'm really not going to worry about it. If data tracking is on the same side of the distinction as taking 1 cent from my bank account, I'm fine with that.