Even though the Europeans used this stitching technique for a longer time, the basting stitches were VERY common on American made hats in the 30's. The reason that you do not see too many hats from that era with them is because they were never meant to be left in. The point of the basting stitch was for shipping hats and stacking them in retail stores. It keeps the ribbon from folding down and over. Most retailers and customers removed them. The hats that seem to still keep them in are the very well preserved hats that most likely weren't worn very much or not at all.
Makes perfect sense. Thanks, Josh.