By default we like to keep FreeLists lists social, so a simple reply from a subscriber will go back to the list for all to see. Usually this is the case subscribers expect – they want everyone to see their reply. In some cases this isn't desired though, so we offer an option to modify this behavior.
If you turn on the reply-to-sender option in your List Configuration, replies will go to the sender and it'll take a Reply-All for the response to go back to the list.