So this is a slight digress, but while we're on the subject, how does an advertiser know that an ad has been successfully served or blocked? I've never had that part fully explained to me. If they're just basing it on number of adds clicks, I rather doubt whether I use an ad blocker or not makes much difference, because I can more or less guarantee that in the ~18 years I have actively surfed the web, the number of ad links I have consciously clicked is between 0 and 5.

So I assume, then, that they have some way of tracking whether the ad was presented to the end-user?