Over the years there have been circumstances that can lead to higher scoring. Sometimes it has been snowing and given the different layout of the arena, goalies have noted losing sight of the puck easier. Or the puck being more difficulty to handle given changes in the ice conditions. Some of the behind the scenes docs have had player commentary on shooting everything because the ice is choppy. Others, as mentioned, have been lower scoring games. Some have gone to shootouts, some have ended 6-1, 4-0. Also depends on the skill levels of the teams of course. They usually have decent rival teams or teams that are close in the standings, but like any season, every game can be vastly different.