I know it's not what this thread is about.. but I have to ask if you are NPIP certified or shipping illegally (intentionally or not)?So I’ve been shipping eggs for a few months and everything was good.
Regarding the eggs breaking.. the ones I received were packaged like yours but with a secondary outside stuffed box protecting the inner box.
USPS does make lots of mistakes as folks have noted. They are the most reliable to my location and also the post masters have gone above and beyond by meeting before or after hours for pick up and calling me from the major town two hours before mine to see if I want to come pick them (chicks) up instead of waiting another day for them to arrive at my location..
Best wishes for successful adventures!