Good observation.
It must be irritating to first time conservatives visitors to this site. FR is known to be one of the best, if not the best, conservative forum, yet they come away with the impression, by taking a cursory look at the threads on RF, that it is a Catholic site. Knowing that the RCC, from Pope to the pew, is flat out liberal, and vote that way. Its common knowledge everywhere. Quite a paradox.
Any FReeper, even a Protestant one, can post as many threads as they want to the Religion Forum. If the forum lacks a Protestant focus, don't look to the Catholics to change that.