They had benefitted from the earlier bad calls.

"The plays added to the Sharks’ frustrations on what they perceive to be a lack of calls or consistency, especially after Joe Thornton was given a one-game suspension on April 15 for an illegal check to the head on Vegas Golden Knights forward Tomas Nosek during Game 3 of that series.

Thornton was suspended for Game 4, a 5-0 Sharks loss that put them in a 3-1 series hole, although the Sharks came back to win the series in seven games. There may also be an internal feeling that some of the human error calls that went in the Sharks’ favor earlier in the playoffs are now being held against them when it comes to reviewing other player safety issues."