It's a very common occurrence at Plattsburgh. With 1200 out of 1924 seats being claimed by season ticket holders, we've had a few attendances of 1600+ where you might be able to count 1.000 bodies if you included players, coaches, rink staffs, press, and one of the homeless guys sitting out behind the rink (kidding about that last part!).
What they're doing for the playoffs, since postseason wasn't included in the season package, is invitng season ticket olders to come in the day before the game to buy heir seat (and only the seats they already had the rights to!), and all unsold seats go on sale to the general public at 5:30 tomorrow (don't get me started on how stupid this ticket system we have at Plattsburgh is...).
I wish they could do it that way all season, but I realize that there are practical issues involved. I know some people who own 5+ season tickets and make sure they're used for every game, and would be more than willing to sell back their seats for a game if they could. I also know some businesses how have 8-10 season tickets, and if they don't have anyone claim them, they sit unused. In hat case, it might be difficult for them to know that they'll be unused in time to sell them back for hte game
Oh well, as Coach Emery likes to say, it means we're a tough ticket get... More competitive than then Red Sux or some nonesense like that
So honestly, count your blessings 5-600 vacant seats in a sellout of 4000 is nothing compared to 6-900 missing out of a crowd of 1900.