...because it is already $400 cheaper than a Studio Display with a comparable stand and will probably end up with a "street price" significantly lower than the announced $1,599 - common practice for any brand that isn't, well, Apple. (I assume that big retailers encourage this practice so that they can pull punters in with big discounts - whereas Apple have their own huge chain of stores, let alone the online store).
If, come Christmas, this still costs $1,599 from Kwik'e'mart, then might be time to declare it a flop - but I wouldn't be entirely surprised to see it going for $999 by black friday (and I'm not talking about membership stores like Costco in the US)