I called Nick, the original Potcoin dev two weeks ago and we discussed this very issue. The Potcoin team is well aware of the legal issues surrounding crypto and River Rock dispensary in Colorado is taking a very cautionary approach to accepting cryptocurrencies for Cannabis. Once you start accepting crypto for Cannabis in a retail business, you are putting yourself under Federal jurisdiction as a money transmitter.
You've been going fine, but now you've stepped into the realm of the blatantly not true.
There's nothing about accepting crypto as a merchant that makes your a money transmitter.
I never said accepting crypto is illegal... I said that a business that goes into exchanging USD for crypto requires a money transmitter license.