This whole analogy is kind of weak. Hiring a plumber to come in and do a job on your sink is similar to hiring a session musician to come in and lay down a bass track on your recording, and not very similar to buying an album.

Buying an album from a musician is similar to buying a book about plumbing that a plumber wrote, and I imagine that most such plumber-writers would indeed have interest in protecting their copyright on their books.

These are entirely different business models, and we software engineers should understand them immediately. It's the difference between running a consulting business and running a product business.