Also, when people say "Friends and Family" I don't think everyone realises just how big that sample is. It's not just friends and family of blizzard employees, but all kinds of random people. For the BC Alpha I remember a bunch of the top WC3 players all having keys, etc.
This is true. "Friends and family" stages can have all sorts of people playing. Anybody from lab guys at Nvidia to the bloke who runs the canteen.