USPS is giving priority to Amazon packages over Chick packages. I can’t for the life of me figure out how mailing live animals with the disfunctional post office system would be a good thing to do. Plus, it is summertime and very hot.
At one time, you could mail children via the post office.
https://www.smithsonianmag.com/smart-news/brief-history-children-sent-through-mail-180959372/
I remember baby chicks being delivered by the USPS as far back as 65 years ago, at least.
many shippers have a temperature limit for live animals due to poor hold ventilation someone cheated and hoped for the best, blame the desk clerk not USPS.