As a person from the USA, I don't understand why the Scots do not wear underwear. I saw a picture of some Scots and one was showing his genitals off. I thought it was a mistake, but was assured that Scots in Kilts do not wear underwear. I think that would be a bit drafty.
Wear whatever you want. I don't care. Neither would 99% of the people out there.
In Berkeley, CA, I see non-Scottish men walking around in skirts, dresses, wigs, evening gowns, etc. all the time. We don't stand on ceremony around here.
Seen plenty of people wear casual kilts who weren't Scotts.
Umm, something you'd like to tell me? o.O
Because it's their culture and society would mock the other male ballerinas. =P
Hang out in Soho and you'll see a few non-Scots skirt wearers.