Uh, this definitely falls under "citation needed". I've lived in SF for the better part of a decade, and I've never personally seen a vacant building that wasn'

Uh, this definitely falls under "citation needed". I've lived in SF for the better part of a decade, and I've never personally seen a vacant building that wasn't vacant for a reason (i.e. condemned, slated for demolition, etc.) These kinds of stories are apocryphal.