I agree with your point, but to the user it can feel like a violation of privacy, and at that point it's not particularly important who's doing it. Whether it'

I agree with your point, but to the user it can feel like a violation of privacy, and at that point it's not particularly important who's doing it. Whether it's the faceless search engine or the faceless retargeting company, the net result is that something you thought was personal and private feels less so.