Alright, after doing some in-depth reading on the matter, I have returned to admit that you are correct. I believe my misconception started years ago when I noticed the voltage on my i pod charger for my car was 12v input (stepped down to 5v output) which I didn't inspect carefully enough.
I did stumble across this article on usb chargers.
http://www.
righto
.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html
(link broken, just remove the spaces around "righto")
Two things I will add to this:
1. Crappy gas station chargers could be a culprit in the bricking and explosion of (standard) vape batteries due to their poorly designed circuitry?
2. Older houses/businesses with outdated wiring or cars that have been diy worked on (stereo amps etc.) can have unexpectedly high voltage.
Either way, apologies for my misconceived notions and for somewhat getting off topic.