This is great. Safari has settings for this but plenty of sites (e.g. yahoo) punch through them anyway. The web has become so incredibly user-hostile in the last decade.
Since the Terms of Service of the Internet running on the National Science Foundation's backbones actually prohibited commercial activity, that put a crimp in the style of people who would try to extract money from its usage, don't you think?
There’s no way to have permissions that depend on things that happen inside the content box / “unsafe zone” that can’t be gamed.