I don't belive a psychic telephone is "witchcraft", nor that wiccan as it truly is intended is bad. It's just pagan mythology, which predates Christian mythology. There is nothing sinister about it, and many of its holidays are now Christian holidays. Neither viewpoint is better or worse than the other, and this country was founded on religious freedom, not any one religion.
That said, yes, McDonald's is not nutrition, and their toys come from many mass-produced tv show or movie tie-ins. Parents should watch what their kids watch on tv and what they are being "sold." To every big business in the world (and that includes politics), we are merely consumers and they like to sell us on anything and everything. McDonald's now has pirate-themed stuff from the new POTC movie. Pirates were lawbreakers and murderers, so surely that is equally bad?
Nevertheless, I believe Lewis did intend the Chronicles to be an allegory to Christian beliefs. He often met with his group of writer friends, the Inklings, and bounced ideas off them. Friend and Inkling member, Tolkien, felt that you could not teach religion by allegory. Lewis did not agree, and he went forward with his allegorical children's book. While he is a favorite literary character of mine (the lion), you also have to be blind not to see Aslan as an allegory to Christ, and the final book as the end of the world. Further up and further in! <img src="/images/graemlins/smile.gif" alt="" />
Nearly everything written by Lewis has some aspect of a former atheist turned Christian in it, which he was. The Screwtape Letters are a conversation between two demons. Under the original poster's flawed analogy, you should boycott one of the greatest and most eloquent literary minds of the 20th century because there are demons in one of his writings.
He would be the first to turn down the idea that any toy or book or tv show should not be enjoyed because of its purported evil content. He was against scholastic snobbery or Christian censorship. He felt all books and all things should be read and that the human mind contained everything in it capable of deriving its own understanding.
Free thought and even books about magic (for there is magic in Chronicles) do not drive a person down toward Satan; they, in fact, lift him up to God.