If the bakery belongs to some church the church has a bit of a problem. Operating a for profit bakery is hard to squeeze through the 401c3 process. Similarly, if he "registers his bakery as a religious institution"...wait, what exactly are you talking about there? What is this "registry" you are talking about? OHHHHH! I get it! You are basically just making up wild feces to support your "oh, we allow discrimination on religious grounds all the time" claim, which is patently false. Let me repeat, since you are apparently unfamiliar with US law: BUSINESSES are not allowed to operate on religious principles that violate the rights of customers.