Convenience, more disposable income becoming more knowledgable over time about the game dev business. As a 16 year old I was relatively poor and didnt think as much about the work and investment that went into games.

Also lack of time, I would never think of pirating a book or game because one will keep me going for ages. I listen to music every day though so until the streaming services come in maintaining a legal music collection as prohibitively expensive.