Google's "I'm feeling lucky" --who uses it, & why?

I don’t get it:
If you click the “feeling lucky” button you get one site.
If the click the other button, you get the SAME site, plus 10 others at an easy glance.
Who uses the “lucky” button? And why is it of equal size (and importance) on the screen? I can, maybe, see a reason for it as a gimicky option, perhaps with a small icon on the side of the screen.

Am I missing out on something here?

I use it when I want a particular business or institution’s website, but don’t know their web address. Last week, I wanted the (Phila.) Art Museum’s website to check on when a particular exhibit would be running – so, “Philadelphia Museum of Art” (feeling lucky) took me right there. One click instead of two.

An interview I read with Google’s founders said that their search page didn’t “look right” with only one button on it. The second button (“I’m feeling lucky”) aesthetically balances the page layout. Hardly anyone uses it.

Neat, huh.

If you put words instead of a URL into the address bar in Mozilla Firefox, it uses Google to give you the same page I’m Feeling Lucky would. I use it the same way Twickster does, but I usually end up having to use the regular search feature. Unlucky me.