Even the 75000 inhabitant city I live in has a balloon shop, but also one for brushes. Also in the neighboring city there used to be a shop just for rubber.
My old small town has one...it is still there after years... This city / village has 14.000 people there. No idea how this shop survives. But it seems to work. Or they are tax evasion scams. Who knows.
They keep most of their inventory uninflated so storage requirements are not that big and the designs keep a long time, and for non-specialists, it's generally not worth keeping bottled Helium around, so it's a pretty decent business I suppose.
