Another thing to think about is vape shops have to compete with online sellers as well, so in order to sell product, profit margins are tight. You only have so much floor/inventory space, so you stick what you know will sell quickly in order to maximize profits. This is how the retail industry works, be it vape supplies or clothing or household goods.
There are a lot of older devices that experienced vapers like, because they work. However, it isn't worth it for <Shop X>to keep inventory because they might sell one or two a month. Most non-"I'm just starting" vapers already have established sources for gear.
Now if a shop was good...they would check with their suppliers and try to get what you need, assuming the suppliers carried it, in a regular quantity, say 2 packs of coils every two weeks or w/e.
But how many shop owners have gone to business school do you think? How well are employees trained, and we've already established that many are just after the cash vs. helping people.
I've been in a shop that the employee didn't even know anything about what they are selling, even when I showed them what I needed. But I've also been in a shop where an employee spent about an hour going over items they carried after I gave them a general idea of what I wanted too.
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