Maybe sometimes. But it can also have a heavy impact in families and communities. Parents looking for kids doing drugs. Relationships destroyed. Lying. Siblings lacking attention when all the attention is on the drug user. Partners of drugs users abandoned – or hurt – physically, emotionally and economically. The same with their kids. Stealing to stop the craving. Murder is knocking on the door . . .
When you have invited substances to take over your mind, you can't be sure that it will let you be the captain on the boat without a heavy fight.
Abuse, violence, stealing and so on are already crimes in their own right, regardless of whether drugs are involved or not. They directly involve harm inflicted on other people. The act of doing drugs does not, so why make that a crime, too?
It's a slippery slope argument, it's like saying cutting yourself should be a crime, because people who cut themselves have issues and could harm others.
Just like drug users, they should be helped, not punished.
When you have invited substances to take over your mind, you can't be sure that it will let you be the captain on the boat without a heavy fight.