Look at it from an economic standpoint. This wouldn't be happening unless the demand for kilts in the marketplace made it profitable for suppliers to offer garments considered kilts (either less expensive replicas of traditional-looking kilts or contemporary designs) at price points below those of bespoke kiltmakers. Now, were I a kiltmaker, who had invested the time in learning how to do it right, I'd be worried about the competition at lower price points, and I think it makes perfect sense for them to seek an AOC (using the French term for wine, cheese, etc.) for, say, "Traditional Scottish Kilt", which could only be used on kilts made in Scotland according to the requirements for the designation.

But for the rest of us, the good news is that the number of people interested in wearing kilts is such that opportunities exist, and have been seized, by manufacturers aiming for a lower price point who make no such claim of "authenticity" (whatever that means). Further, the emergence of contemporary kilts and the success of their manufacturers means that the kilt continues to evolve, just as it has in previous centuries. This is a good thing, because anything which ceases to evolve has become a period piece destined to be marginalised and eventually relegated to the history books.

So, best wishes to the traditional kiltmakers in establishing a brand for their work, and hurrah for the fact that demand for kilts has created a market for suppliers for all kinds of kilts at all price points which sustains a community of suppliers who continue to innovate and, in doing so, broaden the options available to those who consider the kilt something to wear everyday.