the approach i plan on taking is to warn their parents about A) the legal consequences should their children be caught, which would involve tresapssing, b&e, and possession/cultivation of marijuana (a serious charge in this state if not a medical patient), B) the consequences should their children try this on someone not so non-violent as myself, and C) the possibility of a visit from CPS should they allow this behavior to continue.
parts A and B should speak to their concern for their children's well being, if they have any concern. part C should hit home on them personally rather hard.
who knows if the parents are lowlife scum though. it's a roll of the dice, really.