First off, I'm glad that the Cards are not saying anything. It's not going to change anything, other than make them look bad. Glad they're taking the high road.
Second, as far as the dislike for the Steelers, keep in mind that everybody loves the underdog and roots for David to beat Goliath. In most cities in any given year the fans most popular player is the backup QB. We love for a newcomer to defeat the incumbent, and then bash him as soon as he takes office. Rocky, Rudy, and Hoosiers are some of the most popular movies of all time.
Third, once we build David up, we can't wait to tear him down. The Patriots were loved across America when they beat the Rams, and two years later people were saying they were sick of them winning all the time and hoping they would lose.
Fourth, people who post on message boards (self included) or call in to sports talk radio shows are not average fans; they're extremists. They're probably more prone to believe the refs were paid off, the NFL hates them, the networks don't want them, and also become distraught when their team loses. Now have an extreme fan of another team proclaim themselves to be the best ever, and said fan becomes defensive, jealous and envious. The call in shows are flooded, the message boards get tons of comments, and the espn's of the world just got richer.
My biggest problem with that certain segment of Steeler fan - beyond the fact that I found so many of them arrogant and full of themselves even before Sunday's win - is that they tend to be hypocrites. They'll call out Cardinal boards for their treatment of a Steeler fan, yet have zero tolerance for a Cards fan - while claiming they would never ban a visitor just hours after doing exactly that. And they're awfully quick to point they're fingers at others for whining; yet it has been Steeler fans - and players - who continue to whine far more than any others, even to this day, about spygate. Their double standard is both disturbing and laughable.