Is it to feel like your part of their world momentarily? Is there some shodenfreid involved? I think thereis probably a variety of gratifications. One is, by the way, just looking at really hot people. But when i look at angelina joli, i'm not thinking, oh gosh, that don't look as good as angelina jole. She's in a different universe. Even though there's the stars, they're just like us. They are a different category of people.
Also: why do people hate small talk?