I don't think any of these are problems that don't already exist with the way that ads are done.
As the article states, all Google Contributor does is buy the ad impression on the page you're visiting. One way or the other, there will be an ad impression on that page. This doesn't incentivize webmasters to put any more ads on than they already do, as far as I can tell. From their perspective, ads are working normally.
As the article states, all Google Contributor does is buy the ad impression on the page you're visiting. One way or the other, there will be an ad impression on that page. This doesn't incentivize webmasters to put any more ads on than they already do, as far as I can tell. From their perspective, ads are working normally.