You do have to pay for the camp site but if you do not reserve a spot online you can show up and try to find an unreserved spot and then pay when you get there. (there are signs in front of each camp site that say if it reserved or not)
Yes the campground charges for any use of a campsite. Further down road toward spruce knob are several popular trails which have some great tent sites along them. Also nearby is a rather large dispersed camping area with around 20 sites that are free if unoccupied.
Thanks! Your answer is awaiting moderation.