There's a world of difference between two enforcers fighting on the ice and a player running into the stands and fighting fans.
March 29, 2001 Tie Domi of the Toronto Maple Leafs wrestled with a fan in the penalty box in Philadelphia after Domi twice poured water on taunting spectators. The fan lunged against the glass and threw a punch at Domi that didn't connect. A glass panel separating the two collapsed, and the fan was pulled into the box by Domi.
Dec. 23, 1979 Boston Bruins forward Stan Jonathan was hit in the face by an object thrown by a fan, and right wing Terry O'Reilly was harassed by a stick-wielding fan at the end of a 4-3 victory at the New York Rangers. Several Boston players, including O'Reilly and Mike Milbury, went into the stands to fight with spectators. Milbury removed a shoe from a fan and beat him with it.
April 2, 1969 Toronto's Pat Quinn knocked out Boston Bruins great Bobby Orr with a vicious check during an NHL playoff game. A brawl broke out on the ice and in the stands, with Quinn leaving Boston Garden under a heavy police escort.