I am very much aware that people have sex in bathrooms (in restaurants, in bars, on planes). It is actually not a big deal, and one that most establishments treat as a mere nuisance: One restaurant in my area actually had a promotion that hinted that they were open to this.

Filter down to places where you send adults for drinks and the likelihood that anyone is going to treat it as a big deal falls even lower.

THAT is what is unbelievable, your laughable notion that we are sheltered notwithstanding.