The reason for this is that a very large number of automated emails (even if a very small percentage) will bounce back. The person-hours to sort through all of

The reason for this is that a very large number of automated emails (even if a very small percentage) will bounce back. The person-hours to sort through all of that noise are just not worth it in most cases. There are some cases where you can reply to an automated email, but typically it's where the notification is only ever sent to real people with active email accounts - a receipt, not a newsletter.