I would say that journalists have a duty to bottom feed. The 24/7 news cycle makes such slumming inevitable and, actually, "fun." Since wise viewers know that they have to take everything they hear with a grain of salt at this time, they instinctively enjoy comic relief, the levity of, say, an Ann Coulter and a Rush Limbaugh. These people are entertainers and sensible people enjoy seeing just how far such court jesters go in prostituting themselves for the oligarchs or, as is the case of Limbaugh if not quite yet Coulter, self-dealing in tax breaks in order to push the Bush Economic Doctrine of trickle-down, the federal taxation equivalent of a pyramid scheme, a shameful giveaway to the smallest number for the greatest damage to middle class workers and the poor.
Besides, Ann and Rush are such fine specimens of the homo sapien type.
John's "It says more about their audience than anything else" answers the question.
If you know of the normal distribution, you know America has millions of people who live at "the bottom". These bottom-dwelling prey attract the aforementioned bottom-feeding predators.
We ignore the prey at our peril.