Legalized weed might eat away, but if the market is anything like Colorado, it's too expensive vs dark weed. It's so bad in fact that there are projected budget shortfalls because there are few consumers in the space.
Is this fundamental attribution error? Perhaps the reason it is more expensive is because it presents much less of a risk to purchase vs. on the street? It could also be that there is not a lot of competition selling legal weed. Maybe it is because street prices have dropped considerably due to the introduction of legal weed?
Furthermore, it should be noted that Colorado's laws also permit growing and gifting marijuana legally. Why buy it when you can grow it yourself or get it for free from someone who grows it? Sure you can only gift/receive/travel with up to 1 ounce legally and one could also make 16 separate visits (pun intended) to a friends house as well.
Perhaps any or all of these are factors in the price or maybe it is overtaxed to the point that people are still willing to obtain theirs the old-fashioned way.
It's worse in Washington. Legal weed is 3x the cost of medical and 6x the cost of street. It still brings in a vast amount of new consumers who won't pursue other methods, but the other methods will not die off until the price is more competitive.
I think it depends more on the federal government officially deferring to state drug laws (unlikely) or taking action to de-schedule marijuana specifically (slightly less unlikely).
Right now the only people who can grow cannabis openly and "legally" with any degree of safety are the states themselves, which kind of puts a damper on market competition.
I would guess the market pricing for personal quantities of Silk Road weed (including shipping) is more in line with legal/medical prices rather than local black market prices.
http://www.huffingtonpost.com/high-times/marijuana-prices-co... http://khon2.com/2014/04/09/colorado-tax-revenue-on-recreati...