Agaric wants a "create users" permission for Drupal
Key words and phrases
drupal create user should be split out as a permission add users access controlTags
Description
Drupal should add a "create users" permission, split out from administer users, because this is a useful privilege for certain roles to have.
For instance, managers of organic groups should be able to create users that they can then add to their group. They should not be able to administer users (edit or delete existing users).

I totally agree. I asked for this issue in various drupal forum without being answered. Did you find how to manage the question?
It hasn't become pressing enough for us to really try for a solution, but link to some of your posts and maybe we can create (or more likely find) an issue for making these permissions more fine-grained in Drupal 7.