Why does the largest quotidian email not simply eat the others

[cimorene]

My dad's siblings and his aunt and uncle and stepmother found social media didn't work for keeping in contact and instead they each send an email to all the other ones on a little mailing list (just by reply-all, not an actual mailing list software or whatever) about once per day up to a couple of paragraphs full of minutiae such as "We got an inch of rain overnight after a couple of sunny days earlier this week. We went for a walk and there were lots of flowers, including Itemized List of Plants. Spouse has been in the garden for an hour but after that we're going to watch Movie..." It's adorable. They've been going for like 20 years.