Well, I have to disagree.
Quality of stock and finish is just one of many variables that make a deck valuable. In my case, even if obviously I prefer UPSCC, LPCC or EPCC (and I have opted out of some decks because of being MPC), artwork is critical, as is handwork, originality and limitedness (does this word exist?).
I am not going to thoroughly use my cards, but display and look at them. I can't imagine stock and finish quality being part of the experience, maybe just marginally in touch...
I have to agree that registration and printing is another thing, but then again the artworkand its story, originality, custom wrapping, sealing and tuck and short run (stupid, but human to value things others can't have) overcome this issue.
At the end, that's way I paid the money, of course.