Hey Kathryn, I broke into your mailbox at your house and read all your mail for a month, and I shared your Visa bill with your boss and co-workers, and kept copies for myself.
Now do you see the big whoop? OK, maybe not quite the same thing, but in some ways it's actually worse - it's an abuse of trust. It doesn't matter if they do send emails like a bunch of 16 year olds. This is union interference with the people it's purporting to represent. If the team owners had done this to the players, the NHLPA would have (rightly) been down on them like a ton of bricks.
From a techie standpoint, who's the system administrator that allowed the NHLPA mucketymucks access to the players's mailboxes? He'd better be looking for a new job right now. Hopefully he won't find one above the level of fry cook at the local Maccas - I sure as hell wouldn't want to work with somebody like that.