That guild was not stolen by Mood or anyone in it currently, it was stolen by Vaazk when he was convinced that he and his group of friends were going to tower. They didn't, so he gave the Mood to guild (probably at the promise of a hat).

Mood did not know the guild was stolen when he accepted it, and even if he did then it's his own choosing if he decides to keep it. He had nothing to do with it originally getting stolen and it's the original leader's fault. It's not difficult to not get your guild stolen, and anyone who does steal them is an idiot. Mood, Sugar, and the rest of them were not involved in that.