> When an ad network has a strong profile on you, legitimate companies pay good money for those ad slots.

I have looked what interests for example Google stores about me

> http://google.com/ads/preferences

I am very certain that these don't describe me well, or I am classified wrong in some categories (without using any tracking/privacy protection! But I won't actively correct this misclassification).

My experience is rather that some people have very niche interests (among hacker-minded people, the proportion of these people is in my experience much higher than in the general population), and are hard to target using ads, so advertising networks and companies don't make the effort to target these users.

Also, when I google about prices for some product category, I often have other reasons than a buying wish. For example I recently googled about the prices of products in some category because some work colleague claimed that someone else bought a product of a specific vendor for a specific price, but I really felt that the claimed price was off; to substantiate my claims, I did some googling.

Or I google about products in a specific category because I am exactly not satisfied with what some established players that love to advertise have to offer.

That link does not work for me. It closes itself immediately.