Notifications for a team area sent for work items not in this team

I have 1 project with 2 teams.  Team A has area path X and Y. Team B has area path Z.

When I add a notification for Team A, I'm not expecting to receive notifications for work items in area path Z, because Team A does not include area path Z. However work items in Z still trigger the notifications. Is this a bug? Is this intentional?

I use "Deliver to Customer email address" to deliver the message to the Team lead and PM of Team A.

I filter on 'A specific team project', selecting the project.

In filter criteria I have

- State Changes to Done

- OR State Changes to Closed

- OR State changes to Removed

to receive a notification when a ticket is closed or finished.

How can I ensure that the notification is only send for the work items visible to Team A without repeating the area paths in the filter criteria. (In practice, some of our teams have many area paths and it would be error prone to repeat them here)

Thaks