I never have, but as a child I received a couple, and they're great fun. In this case my thoughts are twofold. First, it sounds like the kids are old enough to be potential users of the encyclopedia, and more importantly old enough to start choosing their own sources, and the way I remember it that's a bit past the age at which a cardboard box holds much excitement. Second, the article has a picture of the box that the encyclopedia came in, and it doesn't really look all that large to me; I've gotten larger ones than that from amazon plenty of times and I would expect the author has as well.