Why are some people pyranoid about who they add to their facebook page friends list?

[Curious]

So I know some people. They get along great when they see eachother in public.

But they both have Facebook and neither of them are friends on there, but they sit by eachother and share drinks when they run into eachother.

This makes no sense.

Can someone explain this to me?

[Ainney]

To better their privacy..or probably one of them isn't really that comfortable with each other...