[Powers]

I think the key would be to go back to when they are trapped on the road in the beginning of this season. Before that herd of walkers came they see several dead people in their cars that are not zombies. If every one of them has some head trauma, then the creators were trying to be clever about something. Because other than that, Shane and the prisoner kid, Randall, are the first people we've seen in the series die from "natural" causes