There’s a longer story to this: eBay used to exempt shipping fees from its commissions.

So sellers would be screwing eBay and, being an efficient market, as it often is on eBay, the savings would be passed onto the buyer.

I’d sell games for 1 cent with $10 shipping (cost to me: ~$2) and put the shipping cost in the title for clarity. If you didn’t like it, fine, pay more to buy from someone else.

Now they charge it on the whole purchase, which sucks when they take a ~15% commission on sales taxes and shipping and sellers can’t easily tack on a premium to these. So they get lower net proceeds when selling to someone that has high sales taxes or shipping fees.

This really discourages sellers from shipping internationally where those costs are higher.

Now that eBay charges percentage fees for “promoting” your item and getting visibility, bulk sellers will often post the exact same item, unpromoted, for less if you can be bothered to go through their “other items for sale”.

Have seen some wild examples where a seller sold one item at very different prices. They must have had items with 50% promotion fees, 25%, 5% and 0% (evidently passed onto the customer through different pricing) to capture the whole market.