I was scared while reading the best answer: > Shops know what you buy in what amounts, because nobody buys all the same brands you are getting fingerprinted c

I was scared while reading the best answer: > Shops know what you buy in what amounts, because nobody buys all the same brands you are getting fingerprinted constantly. This is used for targeted advertising, but it can also theoretically be used to track you. I live in france and I wonder if this is even legal here. Even if you change you name, if you start buying some sort of the same combination of grocery article, it can lead back to you if they do some statistics on every people shopping on the globe. Even if you use cash, they can still know that someone bought the same combination of articles somewhere. Not using a smartphone will reduce how you're located. A classic GSM phone can still be located being around a cellphone tower (and more precisely by using triangulation, but it's painful), but smartphones have a tendencies of communicating your GPS coordinates, which allows to track everyone's location at the same time. The amount of hardware required to store all that information must be quite astronomical, but still, a latitude and longitude will be precise and just take 16 bytes at most, which is ridiculous.