Got my friend count up to 30 today

How the fuck do average joes end up with 500 friends on FB? If you aren't a celebrity or in some type of media enterprise (like the Wombat), how can you feel comfortable with all those people having access to your photos and shit?
I know you can limit their accessibility on a group or individual basis but why even befriend them in the first place if that's going to happen?
I know you can limit their accessibility on a group or individual basis but why even befriend them in the first place if that's going to happen?