I've investigated many websites and found lots of them using AdSense against rules (permanently without any penalties). All of the rules violation I reference to Google Ad placement policies and AdSense program policies.
Few basic examples:
- one of the biggest public transport search engine:
Ads on dynamic content, [Ads] Placed on any non-content-based page - Ad on left-bottom is in section without unique and quality content, in addition the result of transport search is dynamically created which is strictly prohibited.
- one of the most popular meme site:
Displaying ads on website with no contextual content is prohibited - many of sites without text content like flash games, images, videos etc. run google AdSense, which they should be banned for infringing rules.
- global leader in translations:
No original and unique content - this type of websites cannot have well prepared content because of it's purpose, why they are allowed to use AdSense so it's text is shredded and have no mutual meaning.
I've also run non-blog site, those Google don't like for contextual ads. Why then some of sites (even the biggest ones) are running AdSense without problem when I'm not allowed to do so?