User blog comment:Kenzen11/The Future Of Character Naming.../@comment-1874924-20111028032606

I think the question of surnames vs. story IDs is best left to each author. I see no need for a formal policy favoring one over the other. (For one thing, there's no reason why an author couldn't use both.) I suspect the main reason most people don't have surnames for their characters is that most actual reality shows identify the contestants only by their first names.

By the by, it's not really true that having a surname is a defining feature of humanity. There are still a number of cultures where many, most, or even all the people either go by only one name or have only a patronym (i.e. a pseudo-name telling who their father was) in place of a proper surname. Rural Afghanistan is an example of the former, and Iceland is an example of the latter. (In Iceland, you're expected to address even total strangers by their first names.)