@imsnif It’s not just the ads; it’s the tracking. Sure the ads are the visible symptom. Many ad blockers (e.g., adblock plus) are actually part of the advertising industry and they unblock folks like Google for money (that’s their business model – see “acceptable ads”). And they usually don’t block trackers, opting for a cosmetic approach. (Assuming you use uBlock Origin, which is good.)
These folks don’t limit themselves to tracking you on the web either. They buy data from brokers, etc.