Bruner likes to keep the best part of the acreage for himself (meaning the company). Which is not to say that everything outside of the 100,000 Shenendoah isn't excellent, but that what Falcon owns 100% of is the cream of the crop.
This is just speculation on my part but I think it may be because when money starts coming in from the JV wells they can apply to the Shenendoah acreage and go ahead with it without a JV partner with 100% going to Falcon. I seem to remember a Falcon presentation mentioning that they were planing to do their own seismic there.
Even if they did take on a JV partner they would be able to get a bigger piece of the pie than the Hess deal.