LigH: He didn't empty "guildhouses" that's a plural. He emptied one guildhouse, which was left open for an entire week. Thieves do that. He also did it on his evil alt. Upon being caught in a different guildhouse, he roleplayed a chase through Hydlaa.
The GMs involved weren't even open to the idea that he had taken his roleplay a bit out of hand, it was decided from the start, without any discussion with him, that he was suddenly an OOC griefer and must be purged from the community. For a roleplay. Sure, not the neatest and most well-conceptualised and planned roleplay, but it was an IC action nonetheless, and he was banned on all accounts.
And so, I have moved from the group supporting PlaneShift's GMs and devs, to the one saying that PlaneShift is not a roleplay game anymore, and should change it's website advertising to reflect this.