You know how sometimes there's a bug on your office window and you're not sure which side the bug is on until you try and smash it? You can stare at the bug all you want. It just isn't clear what side the bug is on until your forefinger acts as judge.
People are like that.
You might be introduced to a perfectly normal-looking couple at a party who, after a few minutes of polite conversation, let it slip that they enjoyed Steve Martin's portrayal of Inspector Clouseau. That, or some other reprehensible belief.
You stare at the couple. For a few minutes you were sure they were part of your world and then - bam! You have abruptly discovered an invisible barrier that will forever separate you.
It is socially acceptable to smash bugs if they are on your office window. I think even a card-carrying PETA member would say bugs on a window are open game.
The same is not true for couples you meet at a party.
How to address this?
It is a conundrum.
There are people in the world who thought Steve Martin was great in the modern version of Pink Panther. And not all of them have sloping foreheads. That is just a fact. Should they be required to wear a scarlet letter? Maybe have something tattooed over their upper lip?
I really don't have the answer.
Bug on the outside of my office window . . . eh.