The arms race between the advertisers and the blockers:
‘30.5 percent of the top 10,000 sites on the web as measured by Alexa are using some sort of ad-blocker detection, and 38.2 percent of the top 1,000… A much larger fraction of websites than previously reported are “worried” about adblockers but many are not employing retaliatory actions against adblocking users yet.
It turns out that many ad providers are offering anti-blocking tech in the form of scripts that produce a variety of “bait” content that’s ad-like — for instance, images or elements named and tagged in such a way that they will trigger ad blockers, tipping the site off. The pattern of blocking, for instance not loading any divs marked “banner_ad” but loading images with “banner” in the description, further illuminates the type and depth of ad blocking being enforced by the browser.
Sites can simply record this for their own purposes (perhaps to gauge the necessity of responding) or redeploy ads in such a way that the detected ad blocker won’t catch….’