Dallas Cowboys Laughing on Return Trip from Philadelphia?

According to a report, the Cowboys were laughing and acting like it was the "last day of school" after the Eagles ended their season. When combined with Tony Romo's "it's just a game" comments, does it look like the Cowboys suffer from a lack of professional pride in their work?

By the way, I'm not an Eagles or a Cowboys fan, and I don't know how true this report is. But the author of this piece who heard the report on Dallas radio makes a lot of interesting points. It's worth a read.