Because Kill All Humans is Beyond Them

Current robots settle for kill all mice or kill all flies. This story about robots with biofuel power supplies. Except, by biofuel, they mean animals not the usual forms of hydrocarbon. No fermenting into ethanol variants with and simple burning like the biofuel found in a car. There's an idea, imagine a car powered by scooping up roadkill. Just kinda gives you the willies don't it. I'm gonna let the exterminators keep this idea. Machines designed to kill somehow come across as more palatable than ones that kill as a secondary function.