Not just budget but also people's dispositions and inclinations. That is, for many people they simply want to pick up an e-cig and hit it, and get that experience. Then once "sold" on e-cigs they might be more inclined to "feel the love" and want to look further into the various devices and mechanisms available for vaping.
But it seems like you really HAVE had a trouble-free road of it. I got an 808 kit, and just like you, spent more and more money trying to make that work. More batts. A personal charger, etc... but in the end it was a PITA and the cartridges and batts were inconsistent. Let's face it, quality control in hand-assembled factories in China is sort of hit and miss.
But even now vaping gear isn't a no-brainer, imo, for those interested in minimizing risks by, say, avoiding plastic tanks [that are at least not the safer polypropylene], and switching from silica to cotton. But I'd bet it will continue to get better. After all, it's still in its infancy. And yes, even a plastic tank is a step way up from smoking.