As noted, depends where you are. In more popular ones, there is a host. In some places, one host will handle several CG's that are close to one another. But we went to McGaffey NFS CG in NM last summer, and even though there were sites with electricity and sewer, no campground host, so having amenities doesn't necessarily equate to having a host. Probably a couple of times a year we run across a NFS CG without a host. Some of these are free and can be remote (do a search on Stunner CG in CO) and some are still run by the NFS who come by and collect the fees and clean the bathrooms every few days.