I sent the above post to SANParks via their webquery facility and promptly received the 5 star reply below.

Thank you Bernard van Lente, Namaqua Park Manager, for a comprehensive, logical and courteous response. Much appreciated. SANParks gets my vote!
"Thank you for your query and concerns.
The area in question was only recently taken over by SANParks and we are still in the process of rehabilitation and establishment of basic infrastructure (compare to the terrible state of the area outside the park- south of the Groen River- for instance). Because the park section is not yet up to standard we do not charge camping fees for now. Work is being done according to a strict business plan and there is still quite a bit to do, however we do not want to deprive visitors of the opportunity to camp here while we are working and hence we allow free camping on a first come, first serve basis for the short term. The tented camps are mostly just local private persons and none of them are tour operators. This problem should go away once there is a reservation system and payment involved.
Our planning is shortly as follows: we are in the process of advertising for the appointment of gate guards. We will start in February 2011 to construct a tourist office at Groen River. Only then can we install the required satellite equipment to manage a reservation system- the existing land lines (farm lines) are completely inadequate for our reservation systems. The system has to be at the coast to allow the relevant staff to check on arrivals, allocations etc. it will probably take up to 6-8 months to get everything in place (completion of offices, gate control etc) and hopefully by December 2011 we will be up and running. There are also some administrative issues which need finalization.
We realize the current situation can be frustrating- it is for us as well. Please keep in mind that this 60 000ha section has been barely more than a year under SANParks control, and that there were no offices, infrastructure, staff or anything else in place when we took over what was previously farmland and a severely abused coastline.
We would in the short term recommend camping out-of-season, then you will probably find you have a whole camp to yourself!
Kind regards".