Difference between a "dancing" kilt and any other, and liners?

[hospitaller]

I have never heard of a longer liner for "dance kilts". Would this be for modesty? Because Highland dancers and Scottish Country Dancers, like Highland Athletes in general always wear some sort of dark colored underwear for modesty' sake.

Cheers

Jamie :ootd:

from pictures I've seen of Scottish Highland Games, underwear or athletic shorts only happen in the US, most if not all male dancers and highland athletes in scotland participate au natural, as a kilt should be worn.