Unfortunately this is due to a Gmail policy.  Formerly that policy was found here:  http://support.google.com/mail/bin/answer.py?hl=en&answer=6588 .  

Not receiving email from groups

When you send mail to any group or mailing list you subscribe to, Gmail automatically skips your inbox and archives the message to save you time and prevent clutter. The message will appear in your inbox if someone responds to it or if there is an error delivering the message. If you'd like to view your message, you can find it in Sent Mail or All Mail.

That link is now outdated but appears to have been replaced with this one:  https://support.google.com/a/answer/1703601?hl=en

Messages sent to email alias or group don't appear in inbox


When I send a message to my email alias, or a group I belong to, it doesn't show up in my inbox.

Example: John's primary email address is sequoia@prettygoodtrees.com. He also has the email alias redwood@prettygoodtrees.com. If John includes redwood@prettygoodtrees.com as a recipient of a message, the message does not appear in his inbox. However, if John sends a message to his primary account (sequoia@prettygoodtrees.com), then the message appears in his inbox.


To prevent clutter, Gmail doesn't route messages that you send to your own alias (or to a group you belong to) to your inbox. You can find the message in Sent Mail or All Mail. If you need to see messages sent to your alias in the Inbox, you can configure the alias as an alternate "Send mail as" address for your account.

There does not seem to be any willingness on Gmail's part to change this policy.  The only workaround for Gmail users is to receive an acknowledgement that their mail was posted, by setting their personal subscription options to ACK NOREPRO.

Answer updated 20191018; verified 20200902