If I'm pointing out adults to my children I generally use Mrs. and Miss. If I'm pointing someone out, it's usually because I know them, at least enough to know their names on sight. If for some reason a child gets the title wrong, adults are far less likely to be offended.
My son's starting to mumble some words. My wife and I call everyone we know by the first name, and the toddler children of my colleagues call my wife and me by our first names, so it seems that teaching first names is fine in the neighborhood. And if there's an administrator living in my apartment complex, they all have PhDs so they can be Dr. Whatever. And the blue collar types who live near me all seem to be on first-name bases with the neighborhood children. And in day-care centers it seems to be the custom to use first names. And eventually when he starts elementary school, he'll call his teachers by whatever name they introduce themselves. And in formal settings, you tend to call people by whatever name they give you. E.g., my wife's green card INS lady introduced herself as "Officer Johnson" so that's how we address her. Seems that all the situations I can think of are either informal, in which case first names are used, or formal, in which case the person introduces himself or herself as "officer" "doctor" "mister" "miss" "lieutenant" or whatever, so this sort of discussion seems kind of irrelevant.
You people are disturbed easily, or at a minimum seem a tad uptight. My wife has her sirname, as it is the custom in her country not to change names. This is a European thing not common in much of the world. Nowadays, some chinese women take on the name of their spouses because it's "modern" and "western" but my wife is from a pretty old-fashioned traditional family and it would have been offensive for her to do so. I must admit I'm a tad old-fashioned, and hoped that she would want to keep her original sirname, so I encouraged her not to change her name. She agreed to keep her original sirname, although if she'd been demanding about changing her name to mine, as many wannabe-western East Asians seem to be, then I'd have to support it. I got lucky in the sense that my wife comes from a culture where it's natural to keep your own sirname after marriage. But my guess is that if you marry a woman who absolutely demands to change her name to yours, you have no choice to accept it.
Anyway, I voted "other" in your poll because I couldn't find the "who cares?" option.
Well it's not only true for East Asians. My wife is a New England Protestant, and she kept her name. We saw no point in her reestablishing her credentials in her career by changing it. I'll admit that it was tough for her in the 1980's when we moved to the Midwest. In particular, we both remember applying for a Marshall Field's card and they had no idea what to do with a married couple with different last names. Fortunately that has changed over the last couple of decades.
I should also clarify my comment about the use of surnames. Generally I use first names with any adult. For friends and associates, the use of a formal title can be fun. This is especially true when I'm in a group of titled folks. I notice that the use of the title by peers is most common when someone is new to that honor. It is almost a bit of a tease.
I do have reason to call upon strangers in public settings in front of other people. I prefer to be even-handed within reason, and so I try for some consistency. For people without other title, but unfamiliar to me, I use Mr. or Ms. This apply to students in a classroom or the public speaking before a board. If there is a specific title that I know I'll use it when introducing or naming someone in a crowd that may not all know the person. However, when I go to someone outside of the formal setting I go back to the first name.
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