I recently added "Ad-block Plus" to my Safari configuration and noticed that all the ads on SE disappeared. Now "Ad-block Plus" maintains a list of sites that comply with their idea of "non-obtrusive." I've never considered SE ads obtrusive,¹ so I would suggest contacting them to get added to their "non-intrusive" list.
¹Unike whoever wrote AdBlock Plus blocking SO ads and bad practice from SO on showing same ad multiple times on same page