Too often moral codes, especially those still largely attached to religious roots, are ascetic and grim. Codes of manners, on the other hand, usually require us to be at least outwardly cheerful, agreeable, gracious, convivial—in short, a contagious source of cheer to others.
Pointer from Don Boudreaux.
I think that codes of manners also can be used to convey respect for others. You are telling people, including strangers, that you conduct yourself with them in mind.
I believe that restraint in the use of four-letter words used to serve this purpose, and it could once again serve this purpose. This puts me at odds with my fellow Baby Boomers and those who came after.