Double Subverted: ...except that they gave him a beatdown anyways.
Parodied: Alice and Bob fight over a water bottle. As Charlie refuses to choose who should take the water bottle, Alice and Bob give him a wedgie.
Zig Zagged: Charlie's neutrality sometimes backfires on him, but over the course of the story, it also sometimes allows him to act as a peacemaker between Alice and Bob.
Charlie doesn't suffer the consequences for choosing no sides.
Or, Charlie picks a side with no problems.
Enforced: The author wants to make a Space Whale Aesop that choosing no side is just as bad as siding with evil.
Lampshaded: "That's what you get for choosing no side, Charlie!"
Invoked: "Say, Alice, since Charlie isn't picking a side, mind if we team up to throttle him?"
Exploited: Charlie has a plan to defeat Alice and Bob, but it will only work if they attack him together at a time of his choosing. Under the appropriate circumstances he goads them both into fighting and refuses to help either.
Defied: "Seriously, I'm not gonna let you two kick my ass for being neutral. I'm gonna kick both of yours!" *beats up both Alice and Bob*
Discussed: "I feel sorry for anyone else who refuses to pick a side."