I have been concerned with this when I owned the 6600. I traded up to the 7700 and the same thing happened. The Accufeed does have a 1/4" foot. You buy it separately, however you can't use the single stitch hole because the needle position is at 5.5 on the Accufeed 1/4 foot.
I just received my new 7700 regular 1/4" foot. They changed the design of the bottom of the foot.
I think the Accufeed system is part of the problem because of the different style of feed dog to accommodate the Accufeed feet. It just causes all kinds of other issues when not using the Accufeed feet.