The "pet project" was the dependency in my example which license would be violated. The contextual author does not care for sure. But generally it is an ethica

The "pet project" was the dependency in my example which license would be violated. The contextual author does not care for sure. But generally it is an ethical problem like you said but also a practical one. Once you stack enough pet (or should I say lpad) projects together something bigger comes out. And the liability is hidden three layers down the dependency tree.