Oh yeah, I forgot to mention the weekend parties! On Sat nites they have some real hum dingers up there. The water patrol is out in full force and its not safe till about 5am Sunday morning.
The grassy area you saw is the campground.

They have a old concrete ball court there that you can park a camper on but like the lady told you, the amenities aren't real good....
The old bath houses used to be by the dock the is beside the ramp. They were finally put out of commision I think... Thats the reason for the porta potties.
Check Hornsby Hollow out. Most of the camp area is rented by the year but sometimes you can find a decent place to camp.