Because a square is dependent on eight people, there are ample opportunities for the square to break down and opportunities to recover it. That's what makes it fun. Class instruction will give you plenty of practice. Also, there are experienced dancers, called Angels, there to help you through. Your primary challenge is to keep your concentration while having a good time.
Demographics varies with each club, primarily based on geographic location.
We are not aware of any published metrics on this topic. This has resulted in a wonderfully diverse club membership. The leadership of the club is similarly split. These events are terrific fun and a great way to see a part of the country you may not have been to. It's also a great way to meet new people.