The bad behaviours you want to be outlawed are in fact already outlawed. It's just super hard to catch and convict on those. While it's a lot easier to prove someone is sleeping rough.
First: We hide the symptoms behind a veneer of illegality which allows us to ignore the underlying causes.
Second: We intentionally write laws which has a proportionally negative effect based on social and medical class of citizens. A class which is already facing hardships.
”The law, in its majestic equality, forbids the rich and poor alike to sleep under bridges, to beg in the streets, and to steal bread.”