Maybe, but my point was that it's often going to be pretty moot, because I suspect that the supplier is not going to detect their error untilit is (in 'reasonable' terms) too late for them to do anything about it.Sure, but you try being the ***hole who tells the customer that no, they can't have it at that surprisingly low price. It's not worth the aggro and the potential bad publicity. Better to just avoid the "sale" in the first place.
Particularly in these days of often very rapid (e.g. 'next day') delivery, it's very likely that a supplier will have 'accepted the order', accepted payment and very possibly despatched the goods before anyone notices the mistake. Once one has got to that point, I would say that, at least for a commercial supplier, it's too late' for them to try to ''backtrack'!
When it's a non-commercial seller, there may be a need for decency/humanity to come into the equation. A few years ago, someone who turned out to be an elderly lady with no previous experience of selling on eBay listed a 'niche item' of substantial value on eBay but made the mistake of not including a 'starting bid' or reserve. Anticipating 'competition', I entered a fairly substantial 'bid'. However, it turned out that it was so 'niche' that no-one else bid, so I ended up 'winning the auction' at a price of 50p. When I discovered the circumstances, I eventually paid her what I regarded as a 'reasonable amount' (albeit less than my 'substantial bid'. However, I probably would not have done that if it were a 'significant commercial seller' I was dealing with.
Kind Regards, John