Its unnecessary but those in the midst of this massive data collection effort have convinced themselves its hypercritical. Context and IP is available with zero tracking and from an advertising perspective, anything more is often superfluous.

Someone reading an auto site or watching a video, healthcare information, makeup guides or a million other things already provides nearly 99% of an advertisers profiling needs, and geolocation delivers finely grained control of delivery. No tracking and behavioral creepiness needed.

All the tracking betrays a certain unhealthy obsessiveness, a desire for control and second guessing and a false belief that knowing an individuals history, race, religion, sex, health data, political beliefs, purchasing history 'somehow' makes things more efficient. But this looks like pursuing an advertising chimera given it has never and will never be a 'neat' science and human behavior is complex. Why not just take the context and immediate interest, and show some basic respect for your fellow humans.