Gotcha. I probably thought the same as you when I first heard about WOZ a few years ago. I even remember calling Jen at JJP about it when they were first taking preorders at $6500.
That was (and still is) a LOT of money for a pinball machine, but it promised to be both the birth of a new company and perhaps the best machine ever (or certainly the most advanced). JJP never called me back to take my order and I quite frankly forgot all about it, since I wasn't really paying attention to pinball much then. Once I actually saw WOZ, I suspected that $6500 was "low" once you accounted for what costs had to be factored in to the machine (all the startup and development costs that Stern had long since accounted for, for one example). Turns out the price was actually $7500 and the $1000 was an early order discount.
Now, at $7500 (also the HOBLE starting price) is/was still 50% more than Stern pins, but I had read somewhere that Jack wanted to build the best pins and cost was to be a secondary factor. So many cool features in the Bally/Williams days had been cut for cost. It's kind of nice to see what a "kitchen sink" pinball machine can be. But that adds significantly to the price.
WOZ isn't a $7500 pin if you don't have all/most of the startup costs in the model. You say you can't wrap your head around paying more than $7500 for a pin? - I still have a hard time when the number is 1/2 that (my NIB MM, RFM, SWE1, Monopoly) were all about that level and I thought those were high at the time.
Is $9000 the new "normal"? I doubt it - I don't see how the business can support that model UNLESS a $9000 pin earns more than double a $4500 pin. But you have to separate the "bling" models from "normal" ones. Home users and collectors are either going to pay more for the bling models or add it themselves later. Operators (generally) aren't going to, because it doesn't bring in any extra revenue for the extra cost.