The emails you are referring to are called email unsubscribe fall back forms. Luminate does not verify whether a record exists in your database before sending these fall back forms. That means that any user who visits your site and accesses an unsubscribe link can produce this fall back email to your organization.

If you see that many emails are originating from users that do not exist in your database, then you may need to audit your site to check for any email messages that are embedded on pages which may be the source of the issue.