Why are records are getting created (I am guessing through Drupal since there are no contributions attached) that are completely blank except for the user's name and email?
- Drupal does NOT store "basic address information" - only username and email address are collected and stored by Drupal "core".
- Basic address info collection (street, city etc) is either done via a CiviCRM profile (and stored in CiviCRM contact-related tables (civicrm_location, civicrm_address).
OR
- they could be collected using another Drupal module (like Drupal profile or CCK or ...).
Drupal's massmailer module, when you add a user to "Create Subscribers" will create a user in civicrm with just an email address.
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