I don't think this is the case. A Netcraft query indicates a privately named nameserver and dns server. This indicates to me that he is running this on his own.
Good point, I didn't look that far.
So we know he's running his own systems. He's most likely capable of maintaining his own Linux box, and he was doing it way before it was popular to buy a Red Hat service agreement, so my bet is that it's home-built. He is running his own DNS servers. Since we know he already uses Linux, the DNS servers are most likely running the open source BIND on Linux.
GE, you find that JR is running open source and you're using it, and you're trying to rid yourself of the extreme cognitive dissonance you're experiencing.
I read a thread called History of Freerepublic written by JimRob himself...he mentions running on his own server several years ago, but never mentions changing over to a hosting service, so I assume this is still the case.
Robinson also said he wrote the software upon which Freerepublic runs, so I doubt if he'd have too much trouble maintaining a server himself.