Big players like YouTube can create detection for that behavior. So it would only harm small sites that are trying to run ads to get by.
I don’t think it harms the publishers. If the ad network (well, Google) does detect it, I think they just won’t pay for the “fraudulent”¹ clicks? (And in best case scenario, you’re actually helping small sites!)
Advertisers on the other hand will pay for nothing, yes. Some of them are small businesses. I wonder if there’s a way to click on big corp ads only...
Edit: ¹ – added scare quotes, see https://github.com/dhowe/AdNauseam/wiki/FAQ#how-does-adnause...
That assumes two things: 1. That such a tool couldn’t be limited to the big players (it could) and 2. That “small sites trying to run ads to get by,” aren’t part of the problem. I can understand why someone would believe this, but I believe the web would be a better place without them. These sites are all pretty much designed (poorly) around their ads, which limits their usefulness. Have you tried looking up recipes online? A bread recipe with 5 ingredients is 30 pages long!!!