Answer:
No. 1) They hurt. 2)You can be kicked out. Then again, yes they're good. You can earn a lot of money if you can deliver a nice knockout. In the end, you get a penalty. Big deal.
It's not that fighting in hockey is a good or bad thing. In an ideal world, there wouldn't be fighting in hockey. However, the fans enjoy a good fight. But fighting in Hockey is not necessary, just accepted.
Fights happen usually for the purpose of doing a job that cannot be done by an official. Refs can control a game only so much. They call penalties to keep the game under control. If they don't call penalties, the game gets out of control and players get violent. Sometimes players deliver gratuitous body checks on the ice. Checking is legal in hockey and also necessary just as blocking and tackling is necessary in football.
Sometimes a player will target skilled players from the other team. Some players get intimidated by this. That's where the "enforcer" comes into play. If a guy is going to deliver massive body checks to skilled players, then he needs to be prepared to "answer the bell".
The enforcer isn't a skilled player. He is there to control through intimidation. Although if he gets a penalty, it will hurt the team. They will be shorthanded.
Hope this helps.