It seems entirely appropriate that on Halloween weekend, the operative word is "Boo!" in Green Bay, where only the most repressed people in town won't want to boo Brett Favre's return.That's the argument I make in today's SN column: Booing Favre isn't bad sportsmanship -- it's cathartic. It's an exorcism -- OK, that's my last Halloween-related metaphor -- for the demons (ugh) represented by Favre's betrayal.Boo him vociferously this weekend, then ...