I don't swap books that often these days, but I recently posted and shipped a few. I do a lot of shipping for other business ventures I have, and use shipping software to manage it all. My post office strongly prefers I use SCAN forms anytime I have more than one or two packages, and I have grown to love them as well, since it is impossible to scan them wrong. 

So with my recent swaps, I didn't want to pay extra for Delivery Confirmation, so I left it off, expecting the labels to print without barcodes. But they printed with barcodes anyway (and I double checked, I was not billed for DC). But they weren't on the SCAN form, so that was annoying because then the clerk had to scan my two SCAN forms and then three books separately (luckily I knew which packages were left off the form). 

My shipping software saved the tracking numbers on those packages, and it looks like they all tracked online except for the delivery scan. Actually what's really funny/odd, I can see all of the tracking except Delivery via my shipping software (ReadyShipper) but when I enter the tracking number in to the USPS website, it won't pull it up. 

Obviously I would pay for DC if it was anything business related, I just think it's funny that USPS seems like they want to track ALL the packages, really you're just paying for the ability to view your tracking via the USPS website. 

I thought everything was tracked these days. We have the option to pay to view the scans or just have the free tracking that only the USPS sees.