The vast majority of homeless in the US historically has been women with children (not and but with) who were not substance abusers. The image of being homeless because of substance abuse was right-wing/neo-liberal propaganda to shift blame to the victims. And just like their spiritual father Goebels said, throw mud and some of it will stick (for generations I might add). The way the image was reinforced was because sub.abusers were more visible, declining shelters when available, or safer out of site places. So people actually saw what they were told. When you see a woman with a cart full of stuff and a kid or two following her on the street you don't identify her as homeless, the sub.abuser laying down in a carton box you do.