We use both. In our area the public land is open for random camping anywhere so we have some favorite spots and when on new tracks we like to set up in out of the way sites. We find quite often the mapped site may be taken so we search for some other spot.
When on trips with upgraded roads or to points of interest/must see tourist attractions I will use private or government campgrounds. Having been in the campground business for over a decade I like to support the entrepreneur and compare notes as to how they set up and manage the sites. And the washrooms, pool and other amenities are nice to use from time to time.
