I walked to the table to apologize and find a way to make them feel welcome. The gentleman was a bit more receptive than his wife who immediately told me the same that she had told the server. "this is disgusting, look at the way people are yelling and it's too bright in here, this is not your steak house this is just your coffee shop"
I informed them of our new initiative to address dress codes and also told them that I could move them into a quieter area of the restaurant, which they refused. I the told them that we would do everything to make them feel welcome and forget that it was noisy or too bright.
I walked away to let the server know my expectations with regards to them and to wow them with his service skills and if that didn't work, to Code Red them. (I'm kidding here, we have no code red - disclaimer)
I actually felt sorry for them. Late seventies, maybe older searching for a bygone era. Working in the casinos in Vegas, you come to meet a lot of the old timers and after engaging in conversation, they always speak of the "good old days" and point at the current ways in which people dress or talk or even going as far a pointing at minorities that somehow don't fit in their world. I know they see the color of my skin when they make these kind of comments, or perhaps they don't or don't care.
Not ten minutes later I saw them walking out the door. I could only thank them for stopping by and wish them a good night. To be so full of anger and unhappiness that you'd be willing to go hungry just because you did not like the ambiance in our restaurant.
Fine dining is: white linens on tables, candles, fresh flowers, subdued lighting, some kind of music fitting of the room, servers in jackets or vests, extensive wine list, etc, etc.
Coffee shop: placemats in place of linen, maybe rolled up silverware, servers in pools or long sleeved shirts, perhaps a tie, two, three page menus, "fun drinks" as options, you get the idea.
Don't go hungry because you may not like the looks of the place, give service a chance, most of the time, that is what makes the fine dining experience possible even in a coffee shop.