I was a Scouter (Scoutmaster) here in Canada for several years, and often saw that very senior Scout leaders would wear kilts, despite it not being part of "official" dress.

There are many photos of Lord Baden-Powell wearing a kilt, and the present Chief Scout of Great Britain doing so, but I would wear it when I took my Cubs or Scouts to Remembrance Day services around Nov 11 at the churches that sponsored us. I used my Scout hose and flashes, and the kilt was my own family one. Always got good comments of course.

Made the gross error of checking it "legality" with Scouts Canada HQ and despite multiculturalism etc - if I was a Sikh I could wear a turban - I was told absolutely to cease and desist. It would have made a fabulous media story - the kind to make people's blood boil - but there was little benefit slamming an organization with lots of problems anyway, that was already downplaying the uniform to make Scouts virtually invisible. Not long afterward my son left Scouts and that was that.
Canada ironically is perhaps more kilt-friendly than Scotland in many respects, so say many Scots.