> Why do you think these industries will evaporate? 

The primary ingredient in a 'hit' will be energy, and there is already a very well established system for delivering energy to individuals in the economy. The devices themselves will essentially be consumer electronic type devices so that demand will be filled by various factories that produce gadgets. Just as heroin use doesn't really change the spoon or syringe markets as those markets are already so large that carrying along the heroin users doesn't really impact them in any meaningful way.

   > Who will make, distribute, and manage the demand 
   > for these devices?

Those folks will still be around, look at your typical smoke shop for a good corollary. But it is a smaller part of the drug industry than the production and distribution of the product.