Surely they're smelly cos they're being eaten by bacteria... Anyway, next dead badger I see I'm gonna check it's head and neck. Maybe. It certainly seems to make sense that fighty badgers would react in this way and that could account for their being far more common than roadkill foxes, for example.
Back to headlights, I remember that in certain Indian forests it's illegal to use main beam so as not to dazzle (and therefore hit) tigers.