I think how a person was raised will have an impact. My Grandmother insisted on giving us etiquette lessons as we were growing up. As in how to dress for dinner, walk around with books on our heads, the whole enchilada! I can still walk, turn, ascend & descend stairs with a dictionary on my head! Out of habit I address all letters in the formal style, (Mr. & Mrs. Robert Lee Smith,or the Smith Family), because that is the way I was taught. Doing otherwise simply doesn't look right to me. Fortunately, my friends understand this quirk.
Running Amok & Causing Mayhem