Several reasons...comfort certainly figures in:
Highland dress and the tartan are among the most powerful, romantic and dramatic of all the symbols of Scotland. It has been claimed that 'a man in a kilt is a man and a half'; there really is something about the wearing of the kilt that confers extra stature on its owner. It is absolutely no coincidence that the kilted 51st Highland Division was rated by the Germans as the most formidable of all the formations they came across during the First World War. Certainly the British government had no doubts on the matter when, after the defeat of Bonnie Prince Charlie, they banned the use of Highland dress and the tartan, which they clearly saw as an incitement to further subversion. Offenders were killed or sent to the colonies. The form of Highland dress has always owed much to the army and it was the Highland regiments which kept the kilt and the tartan alive until at last, in 1782, their use was once more permitted. Before that time, Scots were only permitted to wear any Scottish wear if they joined the British Armed Services. Pipers were permitted to wear their kilt, but usually in a Regimental color. Other service men - most were permitted to wear the balmoral with their clan badge on it. A high price to pay to wear highland clothes, laying their life on the line to do it.
Nowadays, the kilt is seen as the national dress of Scotland. In fact, it started life as NO SUCH THING, being entirely confined to the Highlands. The Lowlanders, who have always made up the majority of Scots, regarded what they considered a "barbarous" form of apparel with'loathing' and 'contempt' and conferred the opprobrious term of 'redshanks' on the Highlanders, who were, they reckoned, what we would now term 'blue' with cold. But today anyone with the smallest claim to Scots ancestry (and not a few without) proudly wears the kilt; even Lowland chiefs and their followers vie with their Highland counterparts in a way which their forefathers would have found incomprehensible and appalling.
https://theauldalliance.com/index.php?pagendx=141&p=a9
