We have agencies to help them ,and also our churches help the ones that have jobs, and need to have a place to live ,while they are saving up for a deposit on a place of their own
I live near a Big 10 uni, and another State uni ,and community colleges ,and a Lutheran college ,so there is a lot of competition for housing.
We have had tent cities ,but they are not allowed ,for health and safety reasons. It is a problem for sure. We probably aren't doing enough ,but it is all down to funding. Some of the homeless actually want to live this way. Why ,I will never understand, but I don't think most people do.