You have have a very uninformed opinion, but it's normal though. If you've never been in a situation where these guys thrive, or never needed this type of aggression, it can seem alien, even scary. What you should probably do is take your cues from the players and coaching staff, and perhaps from the player himself, who has carved quite a unique niche for himself in the league. Talk to other fans and see what they say.
Neil has these altercations all the time, it's part of him exerting his will and character on the other team. He intimidates, fights, hits, and can play a little hockey. You can't put a tiger on the ice and expect him to be a ***** cat half the night. Be happy he picks and chooses his fight times, and hits on the line and not over.
Another problem here is that many posters comment on the rough and tumble aspect of the game with little personal understanding on how these situations work, what it takes to be that guy, and how it makes others feel. Unfortunately people like this tend to be the ones speaking loudest of what they know the least about.
The Hannan scuffle was only pointless to you, because you're sitting in your chair watching the game without applying any character on context to the situation. Unfortunately it's probably not something you'll be able to understand. It is however a byproduct of perceiving the players as little bots moving around on a screen, nothing more.
Personally, I love when the guys scuffle, push and shove, and try and exert themselves on the other team. Its an integral part of the entertainment package that is NHL hockey to me.
