It was a way of implying someone was nuts. Napa wasn't known for wine then, just for mental patients. The hospital had 5,000 in-patients at its peak. Most of them were released when Ronald Reagan was the governor of California and they were supposed to be channeled into community programs, but the homeless problem started at about the same time, so I don't think the communities did much for them. Only the most dangerous (to themselves and to others) patients stayed in the hospital.
