The Green Hat Gang
The hats came from well-known poker player and bar owner Kevin O'Donnell, who owns KO's American Bar & Grill, located in Scottsdale, AZ. Many of the hats, like the one worn by Jason Newburger, come personalized with the player's name or nickname, and are friendly gifts from O'Donnell.
Others were earned, like the one worn by Christine Bielenburg. According to Robbie Runk, who is a bar manager at KO's, Christine won her way into today's tournament by earning enough points to gain entry into a free-roll tournament held at KO's, in which the winner received a buy-in to Event 49.
When the day started, approximately five or six players sported KO's hats, including O'Donnell himself, but only Runk will return tomorrow for Day 2 play, with 19,100 chips.
Runk invites you to stop by KO's and say "Hello," if you're ever in the Scottsdale area.