The Washington initiative passed, but did not really "legalize" cannabis. Only when grown by state-approved cronies (who pay $1000/year) and sold in state-approved crony stores. There would be 25% at three different levels. People could possess no more than 1 oz (already a misdemeanor only) and could not grow for their own use.
The proposed recreational pot stores (like pink unicorns), if they ever come into existence (in some improbable alternate universe), would legally collide with federal law. Participants could be charged with hundreds of years of federal time for becoming part of the Washington State cartel.
The state would have a perverse incentive to shut down already-existing dispensaries, who pay much less in taxes.