I don't expect everyone to believe me on this, because there is just so much myth and romance wrapped up around everything Scottish, but according to the best research we have, it is true.
Actually I do. Working men throughout history usually wore what was appropriate for the job. The heavy leather blacksmith aprons I remember from my youth were at least knee length and wrapped well past the sides of the legs. (even though the smithy was somewhat globular in shape).

Slàinte,