There may not be much money for very long in selling marijuana yourself, but there are probably good "selling shovels to miners" opportunities in providing products and services to help people navigate the "weird" legal and regulatory environment. That environment will stay "weird" for a good long time, probably indefinitely, if regulations regarding other "sin" markets like cigarettes, alcohol, and gambling are any indication.
Yeah, there's a market for consulting and compliance work because it will at the very minimum be regulated, but again - there are huge companies that already do a lot of this work, and once the legal status is cleared up a little more, they'll just expand their existing practices and maybe buy a few boutique companies for their client lists. I'm thinking Big 4 audit / accounting firms here, because that type of compliance work is right up their alley.
His point went far beyond 'consulting and compliance'. "Selling shovels to miners" is spot on - there's hundreds of millions of 'users' worldwide who spend money not only on the actual cannabis but also on items to supports it's use/storage/transportation.
