Indiana Pizzeria Won't Serve Gay Couples

[Norman Humann]

Of course, don't be ridiculous.  Declining someone entry because their attire doesn't meet the standards of your restaurant is legal and amoral.  Declining someone service just because you don't like their sexuality, religion, or race is immoral, and (should be) illegal.

So I can turn away a guy without a jacket, but not the dominatrix and her jacket wearing collared slave (i.e. openly displaying their sexual preferences and identity)?

That's not the same, because you are denying entrance to both of them because of their attire. How do you want to apply that to sexuality? You can tell if someone is gay by their appearance?

If you denied service to the dominatrix while she was wearing suitable attire, that would be a similar situation. But if you present it like this, it's not even an analogy.