Why is there so much secrecy between greek organizations?

[SMSUBear]

I am not greek, but am thinking about it. One thing I have always wondered is why everything about a fraternity or sorority is a secret. I've been told they have secret meetings, and certain things are to be known only by fellow brothers or sisters.

I'm not saying it's wrong or right, I just wanna know why all of these fraternities and sororities are so private and secretive.

If you can't tell me why, I'll understand

SMSUBear