I worked in a fabric dept some years ago. About twice a year we received a shipment of "flat-fold" mill end fabric. It was always folded in one yard folds across the width, then folded in thirds, then in half selvedge to selvedge. This made a nice 12 X22 inch flat fold for display. Of course, the nice folds disappeared as soon as the first customer showed up! Perhaps the fabric you bought was some of this type.