I've done it both ways.

When I started out selling kilts, I carefully pressed each pleat by hand and then packaged the kilt to ship off with no basting stitches. I don't think I ever got a complaint about it, or anyone asking, "Hey, aren't basting stitches supposed to come on this thing?"

On the other hand, kilts the museum has made in Scotland all come with basting stitches in place, and we often have customers ask, "Hey, what's the deal with this white thread at the bottom of my kilt?"

But I would notice on occasion that people would send me pictures of themselves in the new kilt I just made from them, and the pleats would sometimes look quite wrinkled from shipping. Even though no one complained about it, I didn't like that.

So I began to put two, sometimes three (depending on the kilt length) rows of basting stitches in the kilt, before I pressed it. It was an additional step and so added time to the process. But I discovered that it made the pressing go a lot faster, and it really helped the kilt retain its shape during the shipping process. Plus, my clients seem to appreciate the fact that I've taken the extra care to ensure that the kilt arrives to them looking the best it can.

So for some time now I've been shipping all my kilts out with basting stitches in place. If I'm making a kilt for myself, or for someone local who plans on picking it up in person, I don't bother with basting stitches. But if it is going in a box and shipping out, it will have basting stitches every time.