Yet I still find it a better reason than what most murderhobo PC's attack people for: gold or exp. Whether its ironic or not has no bearing on anything. Imminent disasters require action. If there is no other way to get rid of the problem- which in a fantasy setting with nobility will be the ONLY way given the lack of social mobility- that is the only path forward if they refuse to be persuaded. Do you comment on the irony of killing bandits trying to kill you as well?