In Australia using first names is the norm. Adults introduce themselves to children by their first name, the only place they call adults Mr. or Mrs. is in school. Outside of school I've only addressed the very elderly that way and only heard it used with the very elderly, such as in a doctor's office. I've wondered if this is more casual than in the US because of past interactions I've had.
Perhaps, it is more true in the South (US), here we address elders as Mr. or Ms. So-and-so. Children of my friends call me Mr. [First Name]. It denotes both familiarity and respect.
It is impolite to address elders by their first name unless they say it's ok.
Why, specifically, do you believe that advanced age should automatically command what you would consider to be greater respect?
Try to answer without appealing to tradition, please.
I shall take your challenge. Addressing an elder as Mr. or Ms. So-and-so displays a respect for, not only their age, but their life experiences. They have lived longer and experienced much more than a younger person. Elders often have wisdom which comes from trial and error in their earlier years. Listening to them, and respecting them, can often save a younger person much heartache and pain. Sadly, younger people do not often take the time to learn from their elders.
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