I don't know what the logistics are to set this up but I would bet most people would fly in a day early just to hang out. Some of the performing bands would probably be flying in a day early too. Perhaps a small entrance fee to hang out with fellow HC'ers -- at a venue, drinking beer, listening to metal, catching up. Maybe even a local band or two. If not, then perhaps just the local pub? Not that there's anything wrong with the hotel corridor... How many folks would fly in a day early for HC if a pre-party was to be arranged?