Funnily enough, Privacy Badger is an excellent ad blocker. Turns out 99% of ads come from tracking domains. You'd think the ad people would split up the tracking from actually showing the ad, but apparently it's not worth showing an impression without also tracking the user.
Exactly right. Imagine you have a list of 10,000 people who have visited your website whom you want to target with ads. You don't want to show anybody your ad more than ten times. You're using an ad network that reaches ten million people. Your ad will only appear when the trackers tell you that someone is on your target list.
