That all sounds far less organized than what we work with in my classes. It's mostly open, but you shouldn't interrupt folks, nobody should need to shout, and you should give room for others to speak. I've only seen people shift around when multiple workshops were going on, usually resulting in small groups working on different pieces, but that's fairly rare and I've seen most instructors abandon it after the first try due to the amount of noise it produces and the tendency to drift off into discussing daily life and such.
It all sort of operates on the idea that you're actually a nice person, capable of behaving reasonably, and discussing things like an adult (or how we believe adults should discuss things even though this is rarely the case). The idea is to ensure the other person wants to return to what they made, and it's enough for one person to treat the work poorly (perhaps in showing they don't care by focusing on their phone) to bother someone, especially newcomers to workshops.