There was a lot candidates, particularly with the several Black Friday fiascos; but that's more old-fashioned stupidity rather than douchebaggery.
However, my second award goes to a pair of intrepid young hunters in Blount County Tennessee, who hunted and killed two bear cubs while shining a light at night! Black bears are an iconic species, and most people enjoy their sighting, even to the extent of causing traffic jams in the Smokies.
Anyway, there's no eating bears, to my knowledge, so need for food is not an excuse. Just meanness and total douchebaggery. Two guys on pot in the woods shooting willy-nilly.