yes, especially because she says, 'they never answer back' could be a questioning of faith, rather than agnosticism. The whole song is kind of about (to me) what ifs and things she may have done wrong, growing older and maturing. As we grow older we question things more and try to find answers. we question these heavenly creatures and whatever god we were taught to believe it, and when they don't answer back, we must look into ourselves for answers.
Sorry, just a tangent, maybe not exactly what the song is about..
No, no, that's what I took it as. I don't think her song is as shallow as to why the moon doesn't respond when we talk to it (paraphrased, y'know?), or that could just the inner-me thinking and misconstruing what she actually wanted to talk about.
I always took agnosticism as a questioning of faith, iff the person was of faith and turned away--basically wondering whether or not if God (or whatever it is defined as in any religion) exists...Even if it is only slightly right.