Simple. They grew up with the story of Moses, and a Bible full of other prophets, all receiving revelation from God. But those prophets are all safely dead and in the past, and are therefore no threat to the "established order of things". Where "established order of things" = what "we, the establishment (self appointed, thank you) have decided the Bible means". . The idea of a living prophet is intolerable because he would have the authority to say they are wrong.