Different values. I personally think, yoga dance and so on, it is best to have a professional teacher with, in front of the mirror, the action to do the standard, this one is to spend money, the second is only the teacher and students to see. Some people don't want to spend that money, and don't want to make an effort to do well, just learn a little skin and also like to be surrounded by spectators, that is square dancing. As for the grandchildren only around the circle, that even this point of their own interest is no longer, the meaning of her life is completely built on others.
Besides, I really don't think square dancing is fitness. If you've ever done a serious fitness activity, you know that the vast majority of square dances are really neither efficient nor aesthetically pleasing. Doing housework with kids can't even be called exercise, it's called labor.