Hockey fighting

I don't follow hockey much, so perhaps more knowledgeable fans can explain the phenomenon of hockey fighting to me. I enjoy the occasional sports fight as much as the next guy. It reminds me of those times in grade school when someone in the cafeteria would shout "Fight!" and all of us would drop our food and dash over to form a large circle around two kids wrestling and beating the snot out of each other. But in most sports, as on the playground, some authority figure, a teacher or a referee or an umpire, always steps in to try and break things up.
In hockey, as far as I can tell, when two guys start fighting, the refs stand around for a while and let the guys punch each other in the face. If, as some claim, this permissive culture is a ploy to attract more non-hockey aficionados to the sport, I can speak as a non-hockey fan and say that I wouldn't watch a hockey game on television in the hopes of witnessing a fist fight. Brawls play well on Sportscenter, but only as a diversion. The crowd that enjoys and craves that type of spectacle watches WWE.
Hockey works from a disadvantage. It's a difficult sport for young kids to learn because of the scarcity and expense of rinks. There's a reason, I suspect, that so many great players come from Canada and the Soviet Union and Minnesota and the New England area: it's bleeping cold there. It's difficult to appreciate the nuances and rules of a sport when you don't play it growing up. I still don't understand all the rules of hockey, but even many casual sports fans can explain the basics of basketball, baseball, and football. Not so for hockey.
But watching a hockey game live is awesome. I've been to a few Blackhawks games live and realized that the speed and choreography of the game only comes through from a seat near the rink. TV reduces the movements of the players to a block of color moving a few inches across a 36" screen. If I were to suggest a way to turn more fans onto hockey, it would be to offer free tickets to a few games a year to non-fans. Perhaps offer a hockey ticket to the first 10,000 fans attending a baseball/basketball/football game. Pass out a glossy card outlining the basic rules and strategies of hockey at the same time.
And the NHL should put assess stricter penalties for fighting, if nothing but to minimize the chance of incidents like the Bertuzzi cheap shot that broke Steve Moore's neck. Hockey already offers plenty of opportunities for legal big hits, just as in football. Sports are enjoyable for allowing people to walk up and toe the line between aggression and outright violence, but crossing that line should remain a relic of gladiatorial times.