Phones. If a couple scammers can reach every county in the US, so can we.

As if one could break out of the bubble with tech bro "media"

Billboards are only a few thousand per month, and reach most everyone in a metro area. They're also not terribly hard to install/get property with afaict.

Door-to-door canvassing still has pretty high hit rates. You reach other communities by taking a bus.