Behavior
After disabling Notifications in Add-ons >> Configuration under JIRA Service Desk, 'customer' users in Service Desk projects do not receive notifications as reporters on issues.

Expected
Once Service Desk Notifications are disabled, Service Desk projects should utilize the notification scheme defined in their corresponding JIRA project, including 'customers' as issue reporters.

Workaround
Adding the 'customer' users to the administrator project role for the JIRA project associated with the service desk or giving browse permission seems to allow the 'customer' to receive notifications as expected.