There's a very good argument against a basic guaranteed income: money can be spent on a myriad of non-subsistence items, and frequently is in the worse cases of welfare. Guaranteed free housing, food, and clothing, on the other hand, has the advantage of being harder to exchange for drugs (I don't believe that a majority of welfare recipients spend most of their checks on such, but a significant minority do). It's also easier to avoid corruption in a purely governmental program than a government-funded but privately run system, as a basic living stipend would be.