I do not know the source, however, zookeepers do not feed sugary cakes to their animals (especially carnivores who have such short digestive tracts)- they are always made up of various foods from their diet. Also, as someone who uses cardboard boxes to hide dead carcasses as enrichment, I would expect this box to be no different. The wrapping around it might contain interesting smells to stimulate this bears olfactory sense in addition to being another obstacle for the bear. EDIT: I should add that some zookeepers do give sugary candies to apes/monkeys as a way to "win their love" however this practice is HIGHLY frowned upon.