No, But they wouldn’t have access to thousands or maybe millions of dollars that they do now from supplying drugs that are currently illegal.
Companies dealing in tobacco and alcohol make millions or billions of dollars. Why wouldn’t the former drug dealers make that much too in a legal trade of even more addicting substances? They would still be supplying those free first doses to get people hooked.
Collectively these organizations are actually raking in many billions of dollars a year from Americans. Our government estimates that Mexican drug trafficking organizations supply Americans several thousand tons of marijuana every year and several hundred tons of other drugs. There are ridiculous sums of money being made. That's why we keep reading about corruption on both sides of the border, gun battles over smuggling routes, the use of well armed mercenaries like we read about in this article, and so on. The amount of money to be made is mind boggling. People are getting rich in the drug trade and they'll stop at nothing to keep the money rolling in and/or increase their share of the pie.