It's just an example for "dispersed (primitive) camping" in the eastern US. As individual camping near to the nature is nearly not allowed without a special permit, places like Sedalia try to concentrate (and to control?) "wild campers" on special places..
As "wild camping" works well in other countries, like Canada and Scandinavia, even also in more western US regions and Alaska (not to mention China and Russia), it is seemingly not welcome in eastern US, also if you have available the necessary equipment (eg in terms of water and toilet) with you, and you know how to handle them "without traces". - Are eastern campers more dirty campers?