Is the price determined?
What if the developer decides that one gram of cannabis is no longer one cann?
Then the coin dies a terrible death.
He can't really change the peg now.
Though it's worth noting that the Herbal Wellness Center will be accepting CANN for other strains than CANNdy at market exchange rates (ie $15 or whatever worth of CANN, at whatever price CANN is at then).