I don't know. Amazon knows exactly what I bought over the years (ublock or no ublock) and still tries to sell the same or weird stuff to me, or recomends the same books I already bought. I think advertisers just don't care.
Amazon's "also bought" recommendations are usually pretty good in my experience. e.g. "people who bought replacement roomba filters also bought replacement roomba brushes"Usually I find these recommendations fairly sensible.
