Why would you think Blizzard friends and family haven’t played WoW? Do you think these Blizzard peeps randomly pick their grandmas and the neighbor’s 8 year old to invite?
Nah… every single Blizzard employee has at least one or more friends asking them 'Hey man… I sure would love to get a chance to play the beta!" Some of them may very well be people who have played WoW for years.
I’m sure it’s a nice employee perk at Blizzard to be able to invite some of your WoW fanatic friends to beta.
Knowing the right person at right time? I’m sorry to burst your bubble but relationships make the world go around. That’s true in IRL as well as in game.