I interpreted GP's comment to be more about how it's inevitable that businesses track consumer patterns, because after all it's directly their data. Who bought it is usually irrelevant.

That still leaves the purchase data freely available, and if you purchase the same kinds of items regularly you can probably build a profile. The purchase data itself is still valuable and still tracked.

I don’t know about you but when I go to our local supermarket and use cash to buy a beer, the person behind the register kinda sees me and recognizes what I picked. They even happen to know my name as they live in the neighborhood. Do you cover your face when you shop? Because this is the scenario I was talking about.

A bit of a tangent here, but how did you make the quoted text appear differently?

Tell me your secrets! :P

Ah ah, took me a few years before discovering this fine trick.

  You just have to let two empty spaces in front of a sentence. Not less, not more, just 2.