Businesses can choose who to serve based on whether they've been vaccinated or not. An example that comes to mind is a B&B: if a couple of unvaccinated black homosexuals want to stay over, they'll be able to be turned away on the basis that they haven't been vaccinated. Likewise, a cake shop can refuse to bake for an unvaccinated couple wanting a gay wedding celebration cake.
The question is whether the government adds vaccination to the list of protected statuses, like gender, race, religion, sexuality and disability. If they don't, businesses can choose to do what they want.