I'm reminded of the ending of the 2008 film Hancock in which Hancock defaced the moon with a corporate logo. But it was okay because it was "for a good cause".
Okay but my point wasn't about an advertisement or a poster on a wall, it was about advertisements on every blank surface, so I'm not sure your reply is relevent to what I said. If your point is just everything in moderation, I can agree with you, but we're well past the advertisers being moderate with what they're pushing.