The ad consumers experience an externality to the transaction between google and the publisher. The sum of the game may be negative or positive. Which do you think it is, and why?
Google's ads are the single easiest-to-block set of ads in the history of mankind, online or meatspace. The simple fact that most folks don't bother to block then show that either they aren't too negative, or people are so dumb and lazy that humanity is a lost cause anyway.
