"lose control of yourself" is the problem. If you're doing it in public and shitting everywhere, you've lost control of yourself. If you can't work to pay for your habit because you're too zonked to show up, you've lost control of yourself. If you get evicted because you can't work because of your habit, you've lost control of yourself. If you start robbing people to support your habit, you've lost control of yourself. If drugs become your #1 thing in life and nothing else matters, you've lost control of yourself.

They're a scourge because they're make you feel really good. Then they make you feel just good. Then they don't make you feel anything, but if you stop, you feel like shit, so you can't stop. Now you have a lifelong addiction that will never quit nagging you. If you stop for a while then slip up just once, you can OD and die because your body lost some immunity to it. They can grab ahold of anyone at any time. They can make you do really unethical things you never would have done if it wasn't for the habit. It's a really dirty trick. Alcohol is the same way.

If you do drugs and can keep your shit together, power to you. I would just suggest to be mindful of who's in control: you or the habit.

In any other city in America: if you got high on meth in your own apartment, went outside and starting screaming, pooping, and acting belligerent, you would be arrested.

The problem is the antisocial behavior, homeless or not.