And Eric Garner is a great example of how the government with murder you on the _suspicion_ that you aren't paying your taxes. Garner commonly sold individual cigarettes ("loosies") which were usually untaxed; it does not appear he was selling on the day he was choked to death by the NYPD, but rather that he was targeted as a usual suspect.
So we should legalize all of this stuff for adults AND keep the taxes low enough to avoid black markets. Sadly, the folks in favor of "legalization" are often wetting themselves at the thought of the tax revenue.