I had an MM card.  There was no difficulty (other than cost) to obtaining the required letter from the doddering rent-a-doc somebody brought up once or twice a year from California.  Regular doctors won't give one because there are no published standards for medical marijuana use; also because, once they give a few patients a letter they fear heads will descend on their offices and their professional reputations will suffer.  The MM statute itself contains a provision barring law enforcement access to the registry under most circumstances, so I don't understand how the police could have been making "courtesy checks" on certificated growers.  No one ever showed up to check on me.  You're right that there was no legal way to obtain seeds or even cuttings--unless, possibly, you got them from somebody else's MM plant--which just pushes the inconsistency back a step.