why do we find it humorous when a grown man beats up his adolescent daughter? i think it's because the song makes clear that these people are just ignorant hillbillies, and we always find hillbilly violence humorous (feudin fussin & a-fightin, etc). we have also found humor in the spectacle of "darkies" cutting each other with their ubiquitous razors, or of cliche irishmen getting drunk and pounding each other to a pulp. try changing the contexts around -- substituting an anglo-american factory worker (or in claire bear's case, a college professor!) for Paw, for instance, and see how funny it sounds.