Sadly I think a lot of them realize exactly what they're advocating. They're so filled with hate that killing a billion or so people who are seen as subhuman doesn't bother them.
Look, we live in a society of very simple solutions. Depressed? Take a pill. Need information? Google it. Need cash quickly? Go to an ATM.
Why wouldn't it naturally follow: Fearful of muslims? Eliminate them.
Hannah Arendt probably plays into this, but to quote that even greater philosopher, Jello Biafra, "Give me convenience or give me death."