It depends on the FDA...
In my area Oakland Ca. there are much fewer shops, because smoking has been socially ostrcized we have fewer smokers, and so fewer people who turned to vaping to get of cigs, but within a 25 mile radius...maybe a dozen vape shops probablly less.within that radius only 1 shop is what I would consider a "good" vape shop with an experinced knowledgable staff, about 50 diffrent juice companies stocked, gear that goes from beginer to high end.a builder station....
In the same radius I can get cigarettes at every gas station,every corner market,every grocery store,there are alot of discount tobacco shop...but there is only 2 tobacconists whre I can get cigs from around the world...roll your own tobacco,pipes,pipe tobacco, and a wide range of cigars.....
given freedom...I would think that eventually every outlet that now sells cigs would eventually sell packs of coil heads for McNugget tanks, have one or two of the tanks, and a shelf of Mt,Bakers or uncle junks.....and then there would be a few rare Vape shops.....where the more passionate vaper would frequent.