Yes, I had exactly that problem! I never really got into them. I only read one, I think, which was in a pile of library books that my dad got me just before we went on holiday when I was eleven or so. I usually chose my own library books, but I didn't have time to go to the library before we went on holiday, which meant that I had six books that I probably wouldn't have chosen myself to last me two weeks and obviously I'd finished them all before we got as far as the ferry to France, so I pretty much knew them off by heart by the time we got home. And yet I still didn't click that half the S&A stuff was the children's imagination.