Baseball fans everywhere know the unwritten rules of the game.
Such as: When a player loses his grip on the bat while taking a swing and it flies into the stands, the fan who winds up with it returns the bat to the player, who then gives the fan an older bat as a souvenir.
However, as you can see from the video above, when Mariners catcher Kelly Shoppach took a swing and his bat went flying into the stands, a fan collected it and quickly strolled for the exit.
It happened during the seventh inning of an exhibition game on Thursday. Shoppach whiffed on both his swing and on keeping his hands on the bat.