Do bear in mind that this happens to be a fun proof of concept, so it is not endorsed or an official release from the creators of South Park in the first place, and hence, one should not expect plenty of interactive entertainment to be part of the deal. Basically, while in the virtual world of South Park, you will be able to hang around with some townsfolk as well as Officer Barbrady who goes about on his beat in a cruiser, and that’s about it.
Having said that, just to egg you on (pun intended), there is one easter egg level hidden within at the very minimum, see if you are able to find your way in there! I guess with this, it would be somewhat equal to the bus stand from My Neighbor Totoro when it comes to a famous recreation in the world of VR. Interested parties can pick up the simulator for Mac and PC here.