So, you are saying you know for sure that the kilts worn were their own. You never indicated that in the first post. If so I would assume they were wearing the kilt too low, not that the the kilts were being made longer. Any kilt maker I've ever dealt with would not intentionally make the kilt too long. As for the photo above as it is solders I'd have to say that the kilts worn were most likely not made for them, therefore, it would be difficult to use that photo as a guide.