In "a world where the technology exists to make atomically perfect copies", people would still pay a huge premium to have the first instance. Some forgers have managed to produce copies that were, at the time, indistinguishable from originals. But that didn't lead collectors to ignore the distinction. It just made them more nervous ;)

Edit: Another issue is that objects aren't immutable. Let's say that we could make "atomically perfect copies". But those copies would remain "atomically perfect" only briefly. And then they'd be historically distinguishable. And OK, I borrowed that from Hoffstadter's I Am a Strange Loop.