I have anxiety and likely some deep seated depression that would rise up with a vengeance if I didn't have a warm home and access to food. I also love drinking wine, and while I do have access to said home and fridge, this wine hobby is cute and socially acceptable.
Make me homeless and I'd very much represent a mentally ill substance abusing human like Elmo is describing there. They're not 'them'; they're just us in a different reality.