Another issue, at least here, is that police are required to return seized plants to people who don't end up charged or are acquitted. Evidence rooms are full of plants now, I guess, that they are supposed to keep alive, and that isn't really practicable.
The one thing I find a little distressing is how people in other states are so freaked out about everything. A friend was telling me about the experiences of an employee of his, a 20-something young man on extended business in DC in his car with CO plates. He was pulled over several times en route to DC, for no real reason, and then again several times in DC, where his car was finally searched. No pot was found, but there was a spent shotgun shell in his glove box, possession of which I guess is a felony there. He was taken to jail, etc etc, just weird stuff. Instead of Driving While Black, it's now Driving With CO Tags.