A friend of mine moved from the East Coast to teach college in Idaho, and he made the comment that punctuality just wasn't a thing out that way. He's a historian, and he surmised that it was because Idaho never had its society fundamentally altered by industrialization and the time-keeping it required.

But yeah, I try not to get hung up on other folks' timeliness, unless there's going to be a knock-on effect. I know shit happens. I bring a book so I can put my time to good use if I have to wait. An obsession with punctuality in and of itself might be a sign that a person is optimizing what's measured rather than what's actually important.