Some media outlets (most notoriously FoX Propaganda Channel) do exactly that.
The New York Times (at least some of its reporters) have begun doing it too. That's how John Walsh was taken down, and how they spread a bogus story about Richard Blumenthal in 2010.
Yeah, why doesn't the New York Times (Or should I say New York
Crimes) just merge with the Republican party already?! Doing stuff like reporting on obvious and blatant plagiarism from public officials is certainly not the obligation of the media!