Louie G’s Tuesday Trivia Question

I just got back from a quick vacation to Las Vegas. It is something that I think everyone should check off their bucket list at least once in their lifetime. There is so much to do that has nothing to do with gambling.

If you are a people-watching person, Las Vegas is the capital of your world! One day, while walking on the strip I saw something happen that I thought would be a good trivia question.

So, here is today's question:

What name has been given to a group that suddenly assembles in a public place and performs some usually artistic activity such as dancing or a musical item before then dispersing?