Let me open this monologue with an illustratory tale: Once upon a time, my ex (an Atlanta native) and I attended the laser show at Stone Mountain with a couple of yankee transplantee friends. At the highlight of the show the strains of Dixie waft through the humid air of a Georgia summer night. We both dutifully rose, but my reverie was disturbed by the sound of my ex-schmoopie digging his toe into the ribs of his still-placidly-seated counterpart and hissing "Stand up, God damn you! They're playing Dixie!"
Anyhow, reactionary that I am, I'm really big on forms and observances; those mindless customs we perform to show that we are part of the tribe. I stand for Dixie, as well as the Star Spangled Banner and the "Hallelujah Chorus" of Handel's Messiah* (bet you didn't know you were supposed to stand up for that one, did you? Ya bunch of visigoths...) Why do we do this? Well, because we just do, that's why.
Recently on Glock Talk, there was a thread on whether or not ladies should remove their hats during the playing of the National Anthem. A couple of troglodytes displayed their burgeoning patriotism, alongside their complete lack of knowledge of the Flag Code, by opining that Yes, we Should. This was followed by people attempting to delve into the whys and wherefores of this custom, from quoting its origin in religious shows of respect (True: A man doffs his cap to show humility, while a woman keeps her head covered,) to quoting some fruity fashion nabob who stated that it was purely functional and related to the elaborate headgear worn by women of a bygone era, and that a woman wearing a unisex ball cap should remove it. (I've got news for you, Pointdexter: If I quickly doff my "simple unisex ball cap" for the National Anthem, my ponytail holder is going to put out the eye of someone three rows back. If the cap was a fitted one, it will be accompanied in its trajectory by a bobby pin or two.)
The real reason that we, in the present day, remove our headgear if we are non-uniformed males (they salute) or leave it on if we are women is this: Because That's Just The Way It Is Done. If you can't wrap your head around that, then don't try and come over all conservative-like on me, because you're just making things up as you go, ya hippie.
(*: Tradition holds that at the premier of Handel's Messiah, King George II was so moved by the "Hallelujah Chorus" that he stood up. Of course, everyone else present stood because the king was standing. Thus, we stand when it is performed to this day. Whether the tale is true or not makes no nevermind; we stand up because that is what civilized people do when the "Hallelujah Chorus" is performed.)