> If someone wants to get high in their home

That doesn't work in a society in which housing is not guaranteed, and in which almost all "last-resort" housing options (such as shelters) require sobriety. Achieving and maintaining sobriety without stable housing is virtually impossible, and yet somehow society expects everyone to be able to do it and then complains when this doesn't magically happen.

The "tough on crime" mentality says, "well, this should give you an incentive to stop using drugs", except that attitude is completely fantastical: it goes against all clinical evidence of how substance use disorders actually work, and all empirical evidence of what resources a person needs to stop using drugs (assuming that is even the end goal, which is not a given).

To spell it out: if you don't provide housing options for people who use drugs, then you will wind up with homeless people using drugs in public. And criminalizing drug use doesn't change that; it just moves those people "out of sight" to jails and prisons, where they keep using drugs, at a monetary cost to society that is literally orders of magnitude greater than the straightforward option of just giving them housing.