So here's a relevant update: I've actually got some organic peanut butter now. And I must apologize to ket, I would absolutely keep it in the fridge because it does separate and requires stirring every time but 1) the jar says it's optional (says to put it in the refrigerator if you want it to thicken up) and 2) my wife has opted out (prefers it thinner).
Then again, now I'm in the exact circumstances in which I'm supposed to put it in the fridge and I'm still not doing that. So... Maybe I was right from the start?
This is big.
I'd note that I just get the kind of peanut butter that is just ground up peanuts and then season with Maldon salt myself. So yes, it separates, but if you keep it in a jar
upside-down, the oil will at least separate to the bottom of the jar when it is time for use. It's usually not so bad that a quick stir with a standard table knife doesn't have it well mixed again.
So yeah, organic peanut butter, blah blah, but I still don't put it in the fridge.
-wtk