I see your point, but players come from different cultures. In Norway this is actually not so unusual, you see it in many sports.
For me the main thing is that they give everything they have for their team, and I see no reason at all to doubt Zucc´s passion. He truly loves the Rangers, wants to be a Ranger for life, and is desperate to win the cup with the team he considers to be his only true team. If traded, he will be a professional, and give 100% for his new club, but it is no secret that his heart is blue and belongs to the Rangers. I am 100% sure that his "friendly chat" with Kopitar had no effect on his play.
Though, I do think it´s important that the players respect the fans, especially when it comes to team rivalries. So I guess there is a fine line there. But most of the time we don´t see much of this "friendly chatting" between opponents during the games.