I'm told it's basically fermented (not alcoholic) fruit juice, although I have no clue how it works. Sort of sweet-tart syrup? Don't worry, I am very fond of red wine vinegar on my salad but I wouldn't drink it.

I love how much fun there is in Chinese with 'these two things sound the same, instant pun/association' - it makes perfect sense, given the structure of the language, but it still tickles me every time.
Yes, same! And they're also good mnemonics.