Why don't celebrities like to be friends with their fans?

Why don't celebrities like to be friends with their fans? (or not really fans- just ordinary people who aren't famous but not obsessed with them) Don't call me a stalker because I don't like any celebrities. But we are bombarded with them everyday with ads in the internet and on TV. And I get very annoyed when guys always comment on how hot a female celebrity looks. (I'm a girl) But I try not to think of any of those celebrities much- it's not healthy.