The parent comment was replying to a suggestion they partner with organizations who typically help low income and homeless people. I doubt most of them have insurance.
most dont - but you'd be surprised at how many actually do. For example, there are a TON of Vets with PTSD and have coverage through the VA, and MANY are addicts and homeless and low income - but still covered through the VA.
Edit:
Source, experience in this area and my brother is director of the VA health system for the state of Alaska.