Actor Tom Skerritt was born in Detroit, but now lives in Seattle. I can certainly understand his thought process there. Skerritt was the honorary 12th man at a Seahawks game. The 12th man is a ceremony the Seahawks have to honor their fans (the 12th man). This explains the #12 jersey on his Celebrity Jersey Card.
Nate McMillan played 12 excellent seasons with the Seattle Supersonics. He also coached them for another 5 seasons. Eventually, he left Seattle to coach the Portland Trailblazers for another 7 seasons. Despite his time in Portland, McMillan will always be affiliated with Seattle. He received a warm welcome when he raised the 12th Man flag and earned his Celebrity Jersey Card.