The apartment-trashing was entirely senseless. The motive was clearly not theft, for example.
The simplest hypothesis is that the purpose of the crime was to create outrage - in order to destroy the reputation of AirBnB and its business model. It may yet succeed in doing so.
You are aware that there exist nasty people? People who take pleasure in inflicting pain? That's the simplest hypothesis. There's no need to lurch into dark conspiracy theories without any supporting evidence.
On some level, the bad bastards who did it.
Alternatively yes, of course. Building 7, Area 51, Chemtrails etc...