It's not on the buyer in any case because if we enter in an agrement for goods in exchange for payment and the payment was made regardless of the method, then the seller needs to deliver the goods. There is no grey area, the payment was made, the seller has the money. Buyer has no goods, seller needs to ensure the goods are delivered or refund issued. If the seller wants to play the "you didn't get insurance" game, then the buyer should say "you chose a subpar courier service". I have zero tolerance for this kind of fuckery, and I buy insurance anyway whether the buyer pays for it or not because I accept the responsibility to get the goods to the buyer and know the mail service providers don't give 2 shits about customer packages.
1 rule: Don't fuck with other people's money.
This seems to have gotten lost cause people don't get their asses beat anymore for pulling bullshit like this.
Edit: Also, seller tried to place the onus of buying insurance on the buyer, when in fact the seller is the one who trusted the courier to ship without insurance.