Comment by wwwigham

You can use file:// or git:// versioned dependencies in normal npm `package.json`s today. People just don't, outside some edge cases (local packages, nightly versions) because the centralized registry has upsides for discoverability and maintenance. There's also private registries, where you can setup a .npmrc to pull different namespaces from different registries. But if you want, you can totally be that guy who only publishes their packages to their presumably self-hosted repo - it works.