Contemporary music gatherings are cultures of their own, the music may be traditional(or it may not) but the repertoire, playing styles, and of course, the rules of the session are the product of current place and time--

I played in a band for international folkdancing for a number of years, and it struck me that, despite the claims of preserving traditional cultures, the juxtaposition of material would never have occurred in nature--where else would you here "Cotton-Eyed Joe" in a set with "Erev Ba", "Miserlou", a Hambo, "Tri Martolod", and a Finnish dance where people imitate seals-

The other thing is that a folkdancer's favorite Serbian dances may have nothing to do with a Serbian's favorite Serbian dances--