Why do we only sing the first verse of the "Star Spangled Banner"?

[Alex]

I suspect there really isn't a good factual answer beyond, "that's just the way it is settled out over time."

The full version generally takes more than 6 minutes to sing which I suspect is simply longer than most people want to spend on it. And most people suck at singing it anyway so why lengthen the pain. Plus, when engaging in vacuous acts of pseudo-patriotism being too lazy to actually finish it is a nice damning touch. Finally, it would be rude to make old people stand that long, in the hot sun with their hats off, at baseball games.