Questions about Laravel Notifications

I have configured it to send notifications to users who can be members or non-members.

Notifications are sent via email, database, and broadcast.

At this time, if the user is a member, he will receive a notification through e-mail, database, and broadcast, and if the user is a non-member, the user will receive a notification through e-mail.

If the user is a member, the code below is called.

User::find($userId)->notify($notificationInstance);

If the user is a non-member, the code below is called.

Notification::route('mail', $emailAddress)->notify($notificationInstance);

If the user is a member, it works as expected.

However, for non-members, it is transmitted through e-mail and broadcast. Why does broadcast work? Also, why are databases excluded?

...

public function via($notifiable)
{
  if ($notifiable instanceof AnonymousNotifiable) {
    if (Arr::exists($notifiable->routes, 'mail')) {
      $via[] = 'mail';
    }

    if (...) {
      $via[] = '...';
    }
  
    return $via;
  }
}

...

Solved. Here my code.