No, I am more of a fan because I know that home field advantage is something fans can contribute to that can actually influence a game. That means don't boo your players at the start of a game at home. The Seattle fans know how to support their team... morons like you don't. "Duh, I paid for my ticket, I can be as much of an asshole as I want to be." Yes, you can.... and do.
My understanding that Sanchez is practiced with more fire, and confidence this week. So maybe it lite a fire under his ass. I can understand why they would boo him, but I don't think you do it during the pre game. Sets the wrong mind set right from jump.