Read Kaveh Waddell's article entitled Incessant Consumer Surveillance Is Leaking Into Physical Stores. Here's an excerpt:
You just wanted to shop for a birthday gift in peace—instead, you got ads that follow you around the internet, and coupons in your email that remember exactly which products you clicked on. So you shut down your computer, stick your hands into your pockets, and walk to the store. Here, among the throngs of shoppers, you may feel more anonymous than you do behind a screen unburdened by cookies and tracking pixels, and you can browse in peace.
Except not really. If you brought your smartphone, its GPS probably tattled on you before you even walked through the doors. Take your phone out and it might start picking up inaudible sounds broadcast throughout the store to pinpoint your location and send you targeted ads. Surveillance cameras hidden in light fixtures track your movement through the aisles, and could even be using facial-recognition software to understand your preferences and habits and attach them to your personal profile.