My complaint is that there are options for offers on basically all of ebay's selling options, so trying to circumvent other style listings to make offers work doesn't feel above board to me. I do know it's a way to make a nice purchase in some cases, but when you can add a "or best offer" setting to every listing type and the seller doesn't, I think especially when they have a buyout option, making an offer seems like an attempt to cut in line to me.
Sort of semantics, and it's probably more like buying from a local vendor this way, since there's usually a way to wheel and deal. Anyways, even at $1500 it's probably a good scope for the price, I think someone got a nice deal. And yes, if they do cancel it would show up like this too, but as mentioned it effects seller rating as it should.