You know, given lightning was the way Julia tried to bring back Judah Zachery, and given that Collinsport had just so many lightning storms, I wonder why we never did see zombies coming to life?! I suppose we're suppose to believe that lightning never actually struck any graves!!
( That's an interesting question. I used to watch the show fairly regularly and I don't think I ever caught one being rated - but that doesn't mean none ever were...)