That's ducked up. The UK is a million miles from even having the discussion about who can produce the legal shit. The caveman political culture fights it tooth and nail.
In the political system, I think we need to wait a little longer for the last of a particular generation of fascistic, rich, old, white c***s to die off. Then their scumbag baby-boom offspring (who were all coked-up and whatever else in their youth [*cough* David Cameron]) won't have so many scruples about legalization, at least to earn a few bucks off it for them and their cronies.
Then we can worry about the bastard mafia companies shaking everybody down.