Originally Posted by serpens

You can bet that I don't know for sure, but here's my guess. Walmart is specifically excluded from the bonus for Freedom cards, even though (some) Walmart stores code as grocery. I assume Chase has some subroutine that ensures that Walmart does not get the bonus on Freedom cards, and that subroutine was not activated for the Sapphire Reserve. Thus the grocery coding gets the bonus with Sapphire Reserve and not with Freedom.

If I'm wrong, I'll refund all the money you paid me for this guess--and you get to keep the points.