If you rob a store and get caught and get a 100$ fine that's a bit different then if you rob a store and they cut your hand off for example.
Is it?
In the US, there are pretty harsh sentences and yet a high incarceration rate.
Most crimes aren't committed for fun and harsher sentences increase the violence to prevent getting caught but don't prevent the crime a such.
That’s exactly like a prison, but probably with unconstitutionally poor conditions by design, not better than a prison, and probably unconstitutional mechanisms for sending people into them as well.
Better than prison (demonstrated, repeatedly) for dealing with addiction and related crime is funding community treatment for substance use disorders, with studies consistently showing both crime reductions and criminal justice cost savings of several multiples of the marginal funding devoted to drug treatment.
But “tough on crime” via greater criminalization makes an easier political soundbite, even if its manifestly worse at actually dealing with crime.