In its recent promotional press release, the medical marijuana news website blamed the absence of proper banking infrastructure as one of the major reasons why cannabis businesses would move towards other bankable options such as Bitcoin.
Read More: http://www.newsbtc.com/2015/04/17/report-predicts-boom-in-bitcoin-adoption-by-marijuana-dispensaries/
Once MJ is legal, people won't need to hide the fact they are purchasing it.
As long as it is not 100% legal especially at the Federal level, banks will be pressured to not provide credit card merchant services to dispensaries even though these dispensaries are legit at the state level. This is where Bitcoin will step in. It may take some time for cannabis to be legalized federally so there is plenty of time to take advantage of this "grey market".
Isn't there a danger that it will never be legalized at federal level even if most states finally allow it (though I'm guessing there will be a few rouge states who lag behind and actively fight for it to remain illegal)? I just cannot see the old fogies voting to legalize it. What's in it for them? They can still collect taxes from the state tax can't they? Sadly it seems they benefit more from it being illegal to be honest.