[SmirkingRevenge]

Notebooks are a souped up repl, basically. So they might make sense anytime you find yourself turning to a repl. Its also nice to have that environment persist, so that you can pick up where you left off from another machine.

They also make nice front ends for spark clusters (and/or other big data engines).

I agree with the OP though. I wouldn't automate notebook execution as a part of any workflow.