In my case, they also want to know if I get them from my dreams. (Answer: no. Dream logic isn't story logic. Transcribe a dream, and you'll see. Or better yet, tell someone an important dream - 'Well, I was in this house that was also my old school, and there was this nurse and she was really an old witch and then she went away but there was a leaf and I couldn't look at it and I knew if I touched it then something dreadful would happen...' - and watch their eyes glaze over.
In the same vein, dream logic isn't the same as video presentation logic. Who dreams in crossfades, or rotoscoping, or deinterlacing?
*If ya don't know Gaiman wrote a very popular comic called Sandman which was about the lord of dreams and largely took place in 'the dreaming', so that's why people wonder if he gets his ideas from his dreams.

