The closest thing to a bat signal for stoners is the blue lettering of the Cookies logo. When a new storefront comes to a strip mall or a downtown shopping district, fans flock to grand-opening parties, drawn by a love of the brand — one based on more than its reputation for selling extremely potent weed. People often compare Cookies to the streetwear brand Supreme. That’s accurate in one very literal sense — they each sell a lot of hats — and in other, more subjective ones. They share a penchant for collaboration-based marketing; their appeal to mainstream audiences is tied up with their implied connections to illicit subcultures; and they’ve each been expanding rapidly in recent years. All of it is inextricable from Berner, the stage name of Gilbert Milam, 40, Cookies’ co-founder and chief executive, who spent two decades as a rapper with a sideline as a dealer — or as a dealer with a sideline as a rapper. With the company’s success, he is estimated to be one of the wealthiest ...