This happened to me. One day I got 4X the number of clicks that I usually get and none of the extra clicks were from my websites. My websites are all covered by my channels - the extra clicks came from somewhere else. G are such f-wits. I got the same kind of bovine response when I emailed them, just repeated Adsense policies back me about what I can do with my websites, despite me making it clear that the clicks DID NOT COME FROM MY WEBITES. They didn't ban me for it but it's clear how easy it is for someone to game the system with the current implementation.
Anyone interested in writing G about this issue with me? I think the more people that we got to do it, and actually did it We would get a better response. My friend was banned about 3 months back due to invalid clicks - she was brand new to adsense and I was helping her out. She didn't click her own ads, she didn't ask anyone to click her ads - and the clicks that did happen were not from her ONE site, I set up the channels and did all the coding... yet G banned her without a second thought to this. Just wondering how many others have been as well....
They've got at least one letter about it. (sent one it when I posted about the Suggest a feature doohickey a few posts back)
I've felt the same way as the above poster for a long time. It would be real simple to add a 'list of domains' that are to show AdSense ads. If the domain isn't in the users control panel, AdSense ads won't show. Please Google, help protect the publishers who stay above board.