This is just microeconomics: entertainment goods are poor substitutes for each other, and bands like Pink Floyd have monopolies on their own music. When you're

This is just microeconomics: entertainment goods are poor substitutes for each other, and bands like Pink Floyd have monopolies on their own music. When you're in the mood for Pink Floyd, nothing else will do. Similarly, there are many TV shows, but only one Game of Thrones. Many movies, but only one The Godfather. Bridge engineers and architects are good economic substitutes for each other. You can put out an RFP and get competitive bids back.