"Alpha" means that this feature is under active development and not in a particularly functional state. You may be best to avoid it. If you're curious, however, or want to help guide the direction of the feature, feel free to take a peek. Feedback is very welcome.
Mostly for the sake of simplicity. When developing features it can be helpful to test them out in a real live environment. It also seems like it makes for a fun opportunity for users to see how the sausage is made and inform the process.