I make traditional and contemporary styled kilts, on the 8 yard tradional wool ones generally they all hand sewn with the possible exception on the waistband.Sewing by hand is easier for certain things for exmple it would be very difficult to sew the fell by machine invisibly, and sewing by hand allows very small adjustments as you go.
On my modern kilts where I am using canvas/denim fabrics it would be so very hard to sew by hand, and the machine is just a much better option.
It's not always an issue of hand sewn equals better or machine sewn equals worse.I actually enjoy the process of hand sewing,for me it is very much part of the craftsman/tailoring process. To be honest I'm not always sure that completely invisible stitching is all that critical, sometimes being able to see small neat stitches is the mark of good tailoring,infacr many top quality tailors make a point of hand sewn stitches being seen , just to show that the garment has been hand sewn.
Of course there is a cost and time issue as well, but I imagine that many of us could sew a fell by hand just as quickly as by machine!