If I remember correctly, we were just there a month ago, premium sites include a standing charcoal grill. That is the only difference. They may be slightly larger as well, but we had a primitive site and had plenty of room for our 12 person tent. There are no electriticy hookups. The firepit is included with all sites now, a change from the past.
Not sure about electric, but I can tell you that each site has a fire pit but does not come with wood. There are a few places on Route 6 just south of the campground that sell firewood bundles
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