I think you said it yourself: Housing is the basic right that everybody needs to live. Without it, you don't have anything.
As you said, if there is no address; you can't get funds or an education. Then, from a health perspective, so many people are living in very unhealthy situations, physically unhealthy as well as mentally and socially unhealthy. When there are drugs and violence in the area, that just exacerbates things.
To me, it's something that everyone needs. It's obvious, if you look at our health statistics, that people on lower income, living in poor conditions, are much more likely to be sick. They're much more likely to put a greater burden on the health care system, and similarly the justice system, and to drop out of school. I understand that every time a family moves, a child loses three months of school just from making that move. It affects every aspect of life, and it is one of the most basic things. Food, water, shelter and clothing are your basic rights, so that is needed.
The homeless situation and the lack of affordable housing are the tip of the iceberg when we're looking at poverty. That's what we see. Those are the symptoms of poverty.