Because these scammers operate outside the US (think Russia, Eastern Europe, Africa where there are lax to no laws against this type of operation), your state and National Do Not Call Registries are, for the most part, completely ineffective and have no jurisdiction, so I'm not sure how the FCC or government can even go after these scammers.
If enough people report these Scammers, maybe they will get nailed. Rules allow for political calls so they pretend to be one and then "bait and switch" as it were.