Because there are custom decks, alerts, and all kinds of other things that get saved to an account. You setup your own decks and your own chart layers. They get saved to your account so you always get the same layout when you come back.
You can create a demo page for everyone to be able to experience the product without signing-up. You can diable chat messaging in this demo and make it read-only if needed.
Having said that, I genuinely liked the appeal of the product.
