WordPress.org

Is it compatible with Google / Yahoo Publisher / whatever terms of use ?

Yes. It does not modify, alter, change or whatever synonym you'd like your Adsense / YPN code.

Why would I want not to show ads? I want more money!

It's been proven by various analytic articles that regular readers come to your site for your content, and don't click ads. On the other hands, new visitors, or people referred to your site by search engines, are likely to click ads.