I think they get that it's a fictional thing that is useful to get some people asking questions that they might not otherwise find interesting.
That's a good point actually. Q's 1, 2 and 3 are really about determinism and it might be an interesting way to get people thinking about that.
I think Q4 is more about is there anything that isn't natural and what might we mean by saying it isn't.
No, Think that's Q5. The problem with Q4 is that it is asking a question about the nature of an invented plot device and the answer can be changed on the whim of a script writer. For example, The Force is represented as a mystical supernatural thing in the original films but an attempt is made to ground it in fictional science in the first prequel (see midichlorians) but this idea is pretty much forgotten after that.
I think 5 is just trying to get people to think about that too. To be fair there are many posts on here and one humungous thread that are based on some not really understanding any of the questions.
To me "natural" and "non-magical" mean the same thing as do "unnatural" and "magical". Also, the distinction between natural and supernatural is problematic because anything that we used to classify as supernatural but has been shown to be real automatically gets reclassified as natural.
