Kill em off slowly with poisons, no one bats an eye. Kill them even quicker with a bath in molten metal and create beautiful art in the process, everyone looses their minds!!
I promise any of you self righteous gits have a good ant infestation in your yard, wouldn't hesitate to douse them with hardcore poison, and leave em to a slow death. This not only kills 'em off quickly (its molten metal for crying out loud), it creates beautiful and educational art.
I swear some people like to be all hippy and proactive about the world, yet forgot to switch their brain on before the mouth moved into action.