[Eomer of the Rohirrim]

The only point of relevance which I can add just now is this. I remember hearing about a year ago of an assault upon the local bus station. The culprits were clearly Wargs. The event had all the trademarks of a Wargian assault. I would not be at all surprised if Wargs despised man-made transport. As well as sharing the Professor's point of view about toxicity, the invention benefits the race of Men in their struggle against Wargs, a struggle which they have a better chance of winning nowadays.