One of out special stops when we first started traveling was Prairie Dog SP. in Kansas where we were very disappointed with how their prairie dogs were so shy.
The Prairie Dog Town in Lubbock, Texas is a totally different story. I doubt the stone fence is to keep them inside (probably a loosing proposition) but more to keep people out of their special area. The park asks please don't feed them people food and help keep them wild. Although Lubbock is a rather small town their is a constant stream of visitors to watch them.
Prairie Dog Town is also home to a number of other critters most notably the burrowing owl that nests in their burrows in exchange for warning the dogs of snakes and other predators. It is fun to just sit and watch the interaction between the differing personalities.