To be fair, when i bought my first pair of B&O H6 Gen2, it was said NEW and sold by amazon directly. when i got the package it wasnt in an amazon box, was handled by the delivery man as if he opened the box himself. there was missing cables, cat hair all over the headphones, no manuals or bag.. just the headphones in terrible condition. I contacted amazon and they said i bought "used" when it clearly stated in the transaction email "NEW". i was sent a brand new pair of headphones due to the mix up and granted 100$ credit towards another amazon purchase.
Amazon is great when it comes to fixing their mistakes if they're blatantly obvious, but when it comes to something extremely minor they'll say its due to shipping handling or customer damage.
My DT1990 Pros came in mint condition, I think it also comes down to amazons warehouse employees and how they package products.
If its Beyer who sent the product to amazon, they should be mint like mine.
If its sold on amazon from an independent seller/store... the box may of been opened by the store previously and inspected. so that may be the cause as to why you were missing tape perhaps?