Why do I actually have to buy a whole book when I only need the instructions for a single model?

Unfortunately, we can’t do anything about that because the books of instructions came first. Our idea to make life easier for readers of the books by providing ready-to-assemble kits only came later. The authors of the books would quite rightly tell us off if we copied out individual instructions and thus stole them. Our own models (MOCs), however, do include instructions.