[flukus]

The purpose of advertising (with few exceptions) is to manipulate you into buying something you wouldn't have otherwise, or paying more for something than you otherwise would have. Apart from having better things we should be spending my money on (or even saving it, god forbid) advertising is responsible for much of our consumer culture and the environmental problems and other social ills it causes.

Tracking at the moment is mainly to better target the manipulation, but the more data we give them the more they can implement price discrimination. Imagine searching for a USB cable on amazon and because they know you're well off you'll see the expensive name brand options whereas a less wealthy person would be shown the cheap generic ones. Then imagine this becoming more ubiquitous and having to pay a price premium on every purchase based on your profile. To an extent this is already done by geographic location, a store in a wealthy area will often be more expensive for the exact same items than one in a poor area, I'd be willing to bet that a lot of basic produce in your country is cheaper than the exact same produce in my developed one even if it's not produced locally. Even these examples are just scratching the surface of what can be done once they have the data.

If you're from a developing country it might be hard to grasp just how much we spend on things not because they're expensive, but because companies can get away with charging for it.