His mistake was using something as mundane as a restaurant as an example. I like going out to eat as much as the next person, but it’s not a necessity.
Something like medical treatment is. What if a doctor refuses to treat a patient by citing their religion? And that’s the only doctor who is available?
Or what if you live in a small town, where everyone is ultra Christian and everyone conspires to deny you of services because you’re teh evil gay? Because you’re teh evil gay and everyone knows it, you can’t fill prescriptions, buy groceries, go to the movies, buy clothes, and get your car fixed. You not only suffer, but so do your children. What kind of people do they grow up to be, having been treated like second-class citizens their whole life? What does this do to a community, to have a portion of their populace marginalized just because the dominant religion rejects them?