Actually, having been on reddit for over a decade before I left, I'd agree that there is a superiority complex present on reddit when someone asks for clarification on an acronym.
Without fail, if someone used acronyms that might be considered by some to be "common knowledge", and another user asks what that means, they'll get down votes and sometimes even a "are you joking? Everyone knows it means blah blah blah" or similar comment.
I once saw a person get over 50 down votes for asking "what does ETA mean?" when the OP meant "edited to add". I had never seen anyone use it to mean something other than "estimated time of arrival" and was mildly confused by the "ETA" at the top of the comment. Not one single person explained what it meant. Just down votes. I had no idea either at the time, and didn't care enough to do some light searching.
I'd say the business ones are dependent on where you work. I've never worked in a corporate setting where I'd imagine they're more common, so I can't really comment on that part.

Dude... It's SALT.