Yes, the fighting is part of the tradition of hockey. On a practical level, a player is less likely to make a dirty play against an opponent's skill player if he knows that an enforcer will be looking for him later on to fight. Fisticuffs are the tool that the players use to police the game.
The reality is that for many fans of the sport, fighting is an integral part of a hockey game. Indeed, for many a professional player, fights on the ice are anticipated. Although fighting should not be encouraged because of the physical risk presented to players, on the professional level, an outright ban on fighting is unnecessary.
It should not belong in hockey, people have killer themselves after fights, or have developed addiction to ease the pain after fights and it shows poor sportsmanship and sets a bad example for kids. Imagine getting your head beat in while trying to play hockey. Boxing and UFC is different because they use gloves while fighting and they are trained to fight.
No, fighting should not be allowed in hockey because it encourages violence as a part of sport. The game of hockey has rules and regulations, and it should be played according to those rules, just like any other sport. Players who fight exhibit poor sportsmanship and serve as inferior role models to children who watch the games.