How come when you say you know someone who really famous no one ever believes you?

i think people don't belive you because when you think of a celebrity, you think of someone who has a million body guards around them or they live in a secluded area where no one knows your address except a select few (friends, family) plus not a lot of people get the chance to meet celebrities so when you meet someone who has, then they think it's a lie because not a lot of people have.