Ebay has made the situation intolerable by their blind push for 'Free Shipping' across the board - and this latest addition to their money grabbing portfolio is simply adding insult to injury.
For products that are usually just a single item purchase, getting the shipping cost right for various destinations is the only real challenge. If eBay's postage calculator is accurate, then it can take care of the variety of destinations to cover postage ... but that doesn't allow for this extra surcharge, so the seller will have the impossible task of covering it for the variety of situations Countessa as outlined.
However, using the postage calculator is still not what eBay want.
While the fundamental of the tag 'Free Shipping' is understood as a marketing ploy, it is, in fact, a complete fabrication. (I have often heard of Sellers who are still looking for a post office that will send their stuff for free.) More accurate would be the phrase 'Shipping Included'.
Thus, stating 'Free Shipping' actually means adding the shipping cost into the item price. Since this cannot be made variable, the only way a Seller can even attempt to safely offer this is for postal services where distance is irrelevant, which means they are limited to an article no heavier than 500g (be it letter or parcel) - which may cover a great percentage of products on offer, but there is still a huge range of items that are outside this.
Nevertheless, I feel there is a greater evil in the 'Free Shipping' mantra - and that relates to multiple purchases and combined invoices. As I understand it, when issuing a 'combined invoice', a Seller can adjust the invoice (downwards) by an amount up to the shipping costs. You cannot discount the item prices. When the items are already tagged 'Free Shipping', this value is zero, so no adjustment is possible. As a result, the Buyer will be forced to pay for the 'included shipping' on each and every item. This is really a difficult situation - as the buyer will (more than likely) have a reasonable idea of how much the postage should be - and they will be put into a bad mood (just the thing you want pre-DSR).
Even more challenging is when the buyer is well aware of the postage and demands a discount for their multiple 'Free Shipping' purchases because, quite simply, the Seller cannot change the invoice to accommodate such a request. The only way out that I can see - when paying via PayPal - is for the Buyer to pay in full and the Seller to then do a partial refund ... and that's not exactly professional. At least with other forms of payment, the Seller can instruct the buyer to pay a specified amount and then simply mark the eBay invoice as 'Paid'. Some of the problems with this are: that the invoice now does not reflect the truth of the transaction, where some process is required to address the reconciliation headache, as well as fees being charged by eBay on an incorrect, inflated amount.
I have mused upon this aberration and have developed a declaration that would not only be eye-catching, but would also be defendable in court:
CHEAPER THAN
FREE SHIPPING!!**
** For multiple purchases in comparable postal tables when shipped together
But I daresay eBay wouldn't be too happy if it started turning up on listings.....