A mailing list is a way for people to discuss a certain topic through email.
Mail lists have their own address.
When a piece of mail is sent to that address, the message is redistributed to all the members of the list. You shouldn't send posts to the admistrative address, and you should not send administrative requests to the list address. Each address is for a separate function. If you send a post to the admistrative address it will not be distributed to the list, and if you send an administrative request to the list address it will be ignored. This is an address you write to specifically to contact the owner of the list.