Mark Stern once said that it's impossible to be fiscally conservative while simultaneously socially liberal.
Your argument falls into this trap.
Charity will pay for only a small part of the rehab resulting from the pot-headedness that your argument permits.
Instead, taxpayers will pay for the bulk of the rehab, either through outright taxes (obamacare) or rising medical insurance premiums to cover the increased rehab usage.
Not Mark Stern, instead, Mark Steyn.
That is why I would argue for government to stay out of it. But, the pot heads want it both ways - smoke pot, become useless and have someone else support them. That’s nuts!