Joey Bat Flip and the Unwritten Rule

So let me see if I have this right:

Flipping your bat after hitting the winning homer in a critical playoff game: a crime against baseball.

Throwing a hardball 90 mph at a person's ribs: part of the game.

The first action is a demonstration of excitement. It is an outrage.

The second is the equivalent of felonious assault and battery. It's merely a plunking.

Flip your bat and there will be months of ill will and eventual retaliation.

Fire a fastball at a batter's head and there will be a warning. To both teams.

I understand. I just don't understand.