I am an EMS instructor, and ex-paramedic. I remember a quote from my instructor, once upon a time, about judgment of the homeless, particularly the drug-addicted.

"You can question the choices that led them there, but that ship has sailed. The truth of it is if your life consisted of things like looking for food in public garbage cans amongst cigarette butts, bird shit, that had been rained on, that you were reduced to using alleyways to go to the bathroom, newspaper (if you can even find that) to wipe, then it's quite likely that you too would "choose" to retreat to a gorked out haze to escape the emotional pain of that existence. I know I certainly would."