TAS, VOY, ENT and TSFS each made mention of religious officials, activities, or structures.I am not sure Vulcans are truly religious
Plus I think T'Pau was present at Spock anticipated wedding to officiate the wedding ceremony (Spock said there be a ceremony), and she was there as a religious priestess.
When Tuvok's wife said she arranged for the priests at the temple to say prayers for his safe return, who were they praying too? I think the Vulcan gods.Some religions don't have Gods