It makes sense, so it means retrieve repositories only from settings.xml
for that I can do in the RepositoryLookup class :

         List<org.apache.maven.artifact.repository.ArtifactRepository> remoteRepositories = container.getRequest()
                  .getRemoteRepositories();
         remoteRepos.addAll(org.apache.maven.RepositoryUtils.toRepos(remoteRepositories));

would that be ok ?
sorry if I missed again something ...