What are those green mailbox things that aren't really mailboxes and don't even open?

They’re generally used by postal workers to store mail they have picked up along their route for pickup by a truck later. That way the postal worker doesn’t have to lug all that extra mail with him/her all day.

My error. It’s the reverse. The green mailboxes are known as mail relay boxes. They are used by the Postal Service to distribute mail. Carriers pick up the mail from the relay boxes and then visit their appointed rounds. Interestingly, because of reduced mail volume (thank you, email!), some of the boxes are no longer necessary, and some communities have asked the US Postal Service to remove them, as they can attract graffiti.

I always thought that postal workers picked up all the mail in the morning from the post office and then distributed it…I had no idea it was distributed to these green boxes first! So then…what happens with the mail they pick up on their rounds then if that doesn’t go into the green box? Do they just have to lug it around everywhere?

i thought they were Lions glasses receptacles to donate used glasses in