I noticed if there's any allies still left alive within a pretty vast distance, it counts as stealing. When all enemies in a "stronghold" are dead, the icon becomes white.
I.e. that could mean looting grove goblins is forbidden because Saza is still alive. Hypothetically. If the Druids react to you looting the bodies, that would be another issue. Goblin camp stayed red for me, but I blamed that on only knocking out the kids. If you kill an enemy that was only temporarily hostile, it can also get stuck with a red icon.
