Imagine if we were making chocolate chip cookies and rat poison in the same factory. Periodically a family would drop dead after buying a bad batch at the grocery store. Reformers loudly cry out "Can we please stop making chocolate chip cookies next to rat poison!"
Skeptics chime in "Well... It's really not that simple. Even without rat poison, chocolate chip cookies are pretty unhealthy. Do we really want to be sending a message that it's okay to eat cookies by not poisoning them. Wouldn't that just encourage more people to try them. These people knew the risk of rat poison when they choose to eat the cookies, why is it our job to protect them?"
Compassion for other people? We've evolved to have a society for a reason, stepping over dead or desperate people on our way to work isn't good for us either, even if you don't care about them. There are solutions, specifically access to treatment and "clean" drugs that have a much lower chance of killing, that can actually help people.
Inpatient detox will take up to two weeks. After that there is nothing that will make a person to continue except deliberate choice to do so. So access to treatment is OK. "Clean drugs" and "substitute therapy" is already beyond compassion.
Skeptics chime in "Well... It's really not that simple. Even without rat poison, chocolate chip cookies are pretty unhealthy. Do we really want to be sending a message that it's okay to eat cookies by not poisoning them. Wouldn't that just encourage more people to try them. These people knew the risk of rat poison when they choose to eat the cookies, why is it our job to protect them?"