We regularly go to several such in any given season. Some you can get a place with electric if you are there a week early. We never are, so we dry camp and run our own APU a lot. We also use their showers and euphemism as much as we can. If we do it all right, we can make the five days without needing to move. One we rarely miss is the Dulcimer Fest at Evart MI. It is too far from anything to be convenient and jams literally go on all night. In the postings they tell you that there are no "Quiet Hours". If you want quiet, you are in the wrong place.
Matt