Did you see any 20 and 30 amp batteries before vaping? Do you see any other uses for them? Perhaps the auto electrics.
Yes, they're used in cordless power tools, high power flashlights, high intensity back up flood lights, high power hand held lazer pointers and countless other products. I am pretty confident in saying that there are
no batteries that have been manufactured for the specific use of vaping, every single battery in a tube format was made for a purpose other than an electronic cigarette. MOST of those batteries are sent to huge high volume battery pack manufacturers, what has happened since vaping has appeared is that some people are buying large bulk quantities directly from the battery manufacturer as though they were also making battery packs, but instead they just sell the batteries for a profit. This is the reason a large number of LG HE2, Samsung 25R, VTC4 etc are sold with a little sticker applied after the fact that shows the form factor and the mAh specifications, this is because that information is required if the battery is sold as an individual item to a consumer.
There wasn't a large market for the average consumer to purchase them prior to vaping but the market was there, all you had to do was look in the right places, no different than what you would do now. The ONLY difference now is that the market is flooded with counterfeits and websites selling the product at double the MSRP, there are still only a dozen or so suppliers of batteries that I would even think of purchasing from because of the large problem with counterfeit batteries. Vaping has sort of changed it in a negative way too because prior to vaping pretty much no batteries sold worldwide had the pulse rating and ONLY the pulse rating displayed on the wrapper, most of them had nothing on the wrapper but a part number and batch number because they're not meant to be sold as individual batteries!!