This is bad design. I may have come close to doing this as well for the same reason. There is no reason why NPM should auto-register you when you attempt to pub

This is bad design. I may have come close to doing this as well for the same reason. There is no reason why NPM should auto-register you when you attempt to publish (or auto-register when you attempt to sign in) other than to remove a few steps/friction to make it seem like a nice experience. Explicit vs. Implicit : always choose explicit if accidents can cause people serious pain. npm login that is secretly npm "create account" is a serious anti-pattern. And npm publish -> npm login -> npm create account is a consequence of that.