Depending on the time period of the hospital and the situation of the patient, most people would spend their lives in an asylum. If the patient was considered "abandoned" the hospital would need to provide for the burial and most burials were done in somewhat secret circumstances. People with disorders - learning and otherwise - were considered subhuman and to be forgotten when their lives were over. For example; tunnels connecting hospital buildings were designed, early on, so that "civilized" people wouldn't exposed to brutish patients. In 1997, in the town next to where I go to school, they found - well unearthed actually - the long forgotten graves (which were only numbers) of the closed down psych hospital across from the towns middle school. The surveyors found the graves in the woods where they were hoping to expand the school's soccer fields. Patients were lost and locked away in life and hidden and forgotten in death.
This appears to be a hallway in one of the three "N" buildings, on the ground floor. Possibly N-10 because it's in such good shape. It could be one of the othetr "N"s, but on the far side of the main entrances. The farther you go from the sides closest to Bensalem, the better the buildings appear.
The only vagrants I've ever seen in my more-than-20 years of byberry exploration have been friends of mine or young explorers I've never met. No bums, really. Others say they spotted them now and again but not me. I've seen remnants of the homeless there, but they were always long gone.
i think at the time they where more concerned with the patients breaking the glass and cutting themselves with it, so they installed the next best thing.