VANCOUVER — In the pot-friendly city of Vancouver, illegal marijuana dispensaries outnumber Starbucks outlets, and among the most popular is Weeds, Glass and Gifts. There, in a relaxed space reminiscent of the coffee chain, jovial “budtenders” sell coconut chocolate bars infused with marijuana and customers smoke powerful pot concentrates at a sleek dab bar.

When Canada legalized recreational marijuana, on Oct. 17, one of the central aims was to shut down the thousands of illegal dispensaries and black market growers dotting the country. But taming an illegal trade estimated at 5.3 billion Canadian dollars is proving to be daunting.

Many of the products sold at Weeds, Glass and Gifts are banned under the new law, which restricts licensed retailers to selling fresh or dried cannabis, seeds, plants and oil. Yet the retailer’s owner, Don Briere, an ebullient 67-year-old and self-styled pot crusader, has no intention of shutting down his four Vancouver stores or changing his product lineup.

He even has plans for expansion with a new line of outlawed canine marijuana treats, which purport to reduce pet anxiety.