It depends on how you view capitalism, and what you think of the people who make it.
I would first analyze the example of video games, because now a days the publishers suck, and punish those who buy the published versions. Alternatively to buying a game at retail, the consumer can now acquire it illegally with all of the DRM removed, and instead send the money directly to the group who made the game. That way they have a clear conscience and a fully functional game.
Luckily vapes are hardware and not software, so that kind of situation hasn't yet occurred, so you are left with a couple options.
Supporting the manufacturer directly This depends on a couple things, like what are the additional incentives? Are you getting a better price point? Are you getting better features? Are you getting something unique? Better warranty, etc.
Oftentimes you don't get any of this directly from the manufacturer, but you can get all of it from retailers. So very few end up supporting manufacturers. That being said, if you believe a manufacturer has deserved your extra money through some other means: Contributed to advancement in technology, has excellent people skills, devotes time to answering concerns of customers, makes custom equipment for customers, so on and so forth, you may very well be able to justify a purchase from the manufacturer themselves.
It all comes down to what you value.
I value a free market where I'm allowed to make these decisions.