In my auctions I pay insurance on items I do not want to be responsible for say anything over $25 I pay for insurance. It is the buyers duty to buy and deliver payment, it is the sellers duty to sell and deliver product. IN MY OPINION. Sadly, with the advent of eBay all the risk and cost are shifted to the buyer.
The buyer risks sending money on FAITH that the seller will deliver.
The buyer takes risk that SELLER labels it correctly for delivery
The buyer takes risks that the Post Office delivers it
And the Seller wants feedback first so he does not Risk a Negative

What risks does the seller have?

Has payment before shipment
Takes no responsibility for mis-labeled package
Takes no responsibility for Post Office
Takes no responsibility for damage
Takes no risk on feedback
And many gouge buyer for shipping charges

I am a 50/50 Buyer / Seller on eBay... I would hate to eat $75 but I would. But I also would have insured it too to protect ME the seller from eating the costs.

If you order something from a major mail order house and it does not arrive, who eats it? YOU or the seller? Usually, if you are asked to pay for insurance, it is in case of damage on a fragile item.

You must make your own choice on this one….
Just My opinion