Why would I want to give the ad networks additional information and make their advertising more efficient? Given they exist, I’m perfectly okay with advertisers wasting money on badly targeted ads.

Then again, could be fun to screw with them a bit. I wonder what would happen if you just kept clicking I already bought this on everything that pops up. Or better yet, just write a script that clicks it every time one of those ads appears. I wonder if it's possible to go through every single item they advertise and what would happen if you did.

If you want to stick it to the man there is: https://addons.mozilla.org/en-US/firefox/addon/adnauseam/

That clicks all adds for you. Maybe it can be modified somehow to click already bought item?

I suspect that when you do this the following thing happens:

* Big businesses are unaffected as they use click fraud prevention services.

* Businesses that don’t use that have to pay more money to Google because people clicked on their ad, and they think their marketing is effective (at least from a click through perspective).

* Google makes even more money because you are clicking on all the ads and it makes them look better. They can demonstrate how well their marketing platform works even better!

Because some things in life are win win. I actually prefer relevant ads vs irrelevant ads.

Me too, but I also prefer fewer ads over more ads. The more efficient we make ads, the more of them there will (virtually guaranteed) be.

Quantity of ads seems more like a decision for web site operators to make, balancing the wishes of viewers and clients. If a site's ads drown out the content I go there for, I'd give up on the place, but if a site's ads are "too relevant," I'd probably keep going there.