I worked in law yrs ago in Boston and remember when two attys were discussing a case on the train and were overheard by someone client-adjacent. There was a very thorough combing through staff to discuss the matter and stern words issued for all employees to remember they aren't always in private space and everything client or firm related was confidential. With cell phones I think people don't even realize anymore what private space means or that they are blabbing about their hemorrhoids in public.