Interesting... I was looking at the hem on my canvas kilt a little while ago and noticed something. It has sewn-in pleat edges. Though the hem is sewn along it's end with a catch stitch of sorts, it is also sewn down by the edge stitching of the pleats on each pleat.

I can only imagine that the hem must be put in before the pleats are made on any of the kilts with sewn-in pleats, and probably could not be changed without ripping out the stitching of each pleat.

That wouldn't be a problem with the traditional wool kilts, though.