Tinker, true - but it's not difficult for a buyer who knows the system to have an NPB strike lifted. (Someone I know did this to an astonishing degree. I can't give details except to say he used excuses such as "worried about dealing with seller", "just lost my job and can't pay", "tried communicating with seller who was rude", etc., etc. (or in words to that effect - not exactly the same words he used).)
Ah, sellers, think about this: if you are kind and simply give a bad buyer the opportunity for "mutual cancellation", the buyer can give you negative feedback - and it won't be removed by eBay.
He can also refuse to agree to the mutual cancellation request. If he does so, you will lose your FVF. (At least, I've heard that this is so. Can someone confirm, or correct me if I am wrong here?)
I think the whole buying and selling process on eBay has to be considered as markedly different to other purchasing, such as purchasing from a b&m shop. I know what you're saying, Cupie - and of course I agree that the sale isn't final until the goods are received and payment made. But in a b&m shop, the shop owner loses absolutely nothing if a buyer puts goods into a shopping trolley or basket, then ends up not buying them. (It might get the seller's hopes up, of course!) But an eBay seller does lose something.
1. He loses the advertising opportunity for which he's paid. The listing ends; other potential buyers outbid move on; he can't relist immediately - he has to wait until he knows that the buyer isn't going to buy, and that might take 2 weeks.
2. He loses the other interested buyers. As far as they are concerned, the item is sold.
3. He loses time (as said, it could be 2 weeks or more).
Some sellers who sell small items or are a large business are probably not affected by that to any major extent. But hobby sellers may well be affected. They're also the sort of sellers to be least able to defend themselves in a gone-wrong transaction.
Getting back to the shop analogy... I've just thought of this: the situation is more analogous, I think, to someone placing an order for a completely obscure book or something like that; something which the shop must order in specially. If the person ordering is not asked for a deposit when making the order, and tells the shop when informed the book's arrived that "Oh, I don't want it anymore", that's not fair behaviour. I've even heard of people who did have to give a deposit when ordering, and who asked for their DEPOSIT BACK when they changed their minds!
On the subject of people paying later - yes, I've heard some very lovely anecdotes about patient sellers who did finally hear from their buyers, and found that the delay was due to some sort of disaster. Remember when the bushfires and floods created so much worry, grief and upset? So many sellers, fearing that their buyers were in affected areas, tried to give the highest degree of understanding and helpfulness; ditto for buyers who showed the utmost patience and concern rather than annoyance if they felt their sellers were in some of those dangerous areas.
We all pulled together, all of Australia.