Feel free to elaborate.
It was my understanding that weed itself isn't harmful that many ways, except for the inhalation of the smoke which of course is bad for you.
The only economic factor I can imagine is big-wig people trying to keep money growing trees because it's more expensive, looking at it from a different angle would be that society would benefit from it as they then could tax the shit out of it just like alcohol and therefore making a money in the long run.