When we put on costumes at Halloween, we dress up as unusual sorts of people; they are not at all randomly selected from real folks, or even from fictional characters. Instead, we prefer to dress up as people whose style of dress says a lot about them, i.e., people with vivid and well-defined roles strongly indicated by the way they dress. Knowing that someone is a princess, athlete, fireman, doc, pirate, or prostitute says a lot about more about their personality and lifestyle than knowing that someone is an insurance adjuster, sales clerk, or network administrator.
This is interestingly at odds with of our general tendency to avoid regimentation and structure, though we accept more at work than at home. It seems that at some level we miss and/or admire folks whose lives are tightly structured and defined by a particular strong standard identity. Or at least we admire them when their role has high status, like docs, athletes, etc. How much have we lost by not having the better-defined social roles of our ancestors?
Added 1Nov: When I started Overcoming Bias, I also sketched out this other blog concept that I never used, using me in costume in the header:
cute costume, dad
The most unusual costume I saw on any of the kidlets that came to my door on Halloween this year was one I initially thought was "Mario", of the Super Mario Bros. series of Nintendo games. It entailed some sort of red-hued coverall-type shirt, a hat, and a painted-on mustache. But on closer examination I saw that this kid (a boy of maybe nine years old) had a logo on his shirt reading "Santa Clara University Facilities". My guess is that maybe one of his parents worked in facilities at SCU and he was dressing that way to emulate them, because otherwise I don't know where a kid of about 9 would get such an idea.