People are very divisive over whether this should or could be a proper usage of punctuation, and I think we’re missing the larger issue. Grammar is not by necessity prescriptive. The variety of writers who have chosen to use it differently and have become popular makes this clear. The issue is whether or not a story is both readable and effective in the style in which it’s written. Cormac McCarthy’s stories are both, whether or not you actually personally like them. They’re spare vast landscapes of tales and they use grammar just as sparingly.