[dobbsbob]

Most gangs are not directly involved in the sale of narcotics, instead they are involved in extortion "taxing" those who are selling drugs in their area. If drugs disappear they will find another black market to tax like gambling, fencing stolen goods or selling weapons. However the difference is they won't make a million dollars per month taxing somebody running an illegal gambling operation unlike jacking cocaine drivers. It will be a much smaller criminal enterprise, they won't be able to afford a small army of thugs to terrorize an entire city like they currently do here now with all their windfall narco profits.

As for non violent street peddlers I imagine they will go into exports, shipping narcotics to countries where it's still illegal. After Marijuana was symbolically decriminalized by police here refusing to arrest people for possession, and the black market was swamped with declining prices, many former dealers and growers instead decided to operate unlicensed tourist operations selling weed travel packages, and running their own storefronts for legal drugs using their profits as street dealers to bootstrap it.