And then there’s Björk’s 2011 concept album Biophilia. By all accounts, this is one heck of a gesamtkunstwerk! The album was conceived and recorded between 2008-2011, inspired somewhat by the work of her environmental organization, the Náttúra Foundation, and explores the links between nature, technology and music. The album was also released on ten interactive mutimedia apps (one per song) that link the themes of the album to concepts in musicology.
This isn’t to say that we only like songs because our brains are lazy. It has to do with how our brains process new information as it fits into a given context, in this case, how melodic notes fit into a key.