So, Angelina whatshername adopting a Cambodian kid is important to the survival of our species?"Why do we as people drool over Celebrities?" I'd say that's not quite the right question. It's as apes that we drool over celebrities, because it makes good evolutionary sense in terms of survival and reproductive chances to be obsequious towards high status members of the group.
Same for Elin and Tiger Woods' divorce? Or what Julia Roberts wore to the last Oscar? lol