I'm really wrestling with this, because I can see two sides of the argument. On the one hand, I'm as cold-hearted about some things as you could be; it galls me to pay taxes for some of this nonsense.
However, on the other hand, I know personally that it's not just the street trash types that get into this trouble. A few years ago my very honorable, gentle, friendly, well-off mother had to take some opioid medication after surgery, and after a few months (long after we forgot about the original surgery) we found out she was "doctor shopping" to get additional prescriptions that her primary wouldn't give her. If she lived alone, instead of in a solid marriage with my dad and plenty of family support to help her recover, she could easily have fallen into hard drug abuse initially just to kill the pain but ultimately living that street life. And we all know that drug users relapse, so just escaping once isn't always the fix.
Statistics show that just ONE month of opioid drug use can lead to something like a 30% chance of abuse. Even a one day prescription can lead to a 6% chance they'll still be "using" a year later. Is there any wonder the rates are so high?
http://www.newsweek.com/cdc-opiate-addiction-572498
So how do you assign value to one life over another?
That "street trash" homeless lady you're willing to sacrifice is someone's mom, wife, grandmother, friend. That diabetic multiple amputatee that someone used as an example? He's a dad, grandfather, friend, deacon... how can you set a low value on his life?
No, we have to value life, no matter how painful the process, and find some way to deal with the ugly that goes along with it. With the odds of addiction so high for a relatively common drug, the chances YOU may need such help are far from zero. "Do unto others", and all that.