Well you could classify it as a secondary reason. Stopping her would have also stopped her getting arrested
There's no guarantee of that at all.
All Damp would've done was told his parents that she'd pinched a bottle of wine.
Whether they then punished her or not, who knows.
And whether punishing her or not would have meant she didn't then go out and get drunk and throw bricks at houses is something none of us can know.
At the very least Damp should have told his parents so that they were aware of the situation, but whether he told or not doesn't actually guarantee an affect on whether this event happened or not.