My point stands. Uber has been a public company for all of 5 hours now, and their stock is a few dollars less per share than it opened, and everybody is freaking out and wondering what it all means.
It's not about planning out 10,000 years, or even 100; it's something more abstract than that. What will your legacy be? Your family's legacy? Your country's? Humanity's? I don't have any personal connection to somebody who will be alive 1000 years from now, or even 200, but I still don't want to leave them a dead, depleted planet.
Is the clock a bit frivolous? Sure. But it's not about the clock. The clock is merely a symbol, that we have considered our place in history, that we recognize we are part of something larger, and we want to be good stewards of our future.