Can't directly quote the member who wrote this, since I have him on ignore, but I saw the question posed as a quote in a reply:
For anyone concerned about legalization costing the taxpayers, one of the most compelling reasons for legalization (and one of the biggest reasons why it's getting traction now, IMO), is because it's a net-positive on the budget. Just on direct costs, the government can make way more in taxes on the sale of marijuana than it costs to legalize. Not to even mention the indirect benefits assocatied with no longer imprisoning millions of nonviolent offenders.
Even the skeptics out there are only debating
how profitable it will be; nobody is even trying to claim that it won't be profitable
Even if demand remains completely static (which is absurd, but let's assume it), legalizing it would just take the revenue out of criminals' hands and turn it into government revenue. Does anyone actually think that's a bad thing?