@drekly, simple ads are not a problem, if they are based on the content of the page and not based on user logs. Ads as is only can be somewhat annoying if there a lot in the page or they appears in the middle of a concert in YT, but no are a risk for the user privacy, no more than a commercial poster in the street or an ad in TV. As with all, bad the abuse. Years ago you saw 1-2 banners in a page, but novadays you must seek the webcontent between advertisings, banners, cookieadvices and popups