After only reading the OP, not the discussion on it, I feel that he was within his rights.

I feel that is legitimate, from a choice standpoint. Now, as a justice of the peace, a public official to serve the public, is another matter. I think, if the couple were truly and completely inconvenienced, then at most he should lose his job. If that. I'd want to see where it says he has either the right or not to choose not to issue a license before making a commitment on either side.