Ah, but the iPad materials (unlike an Audi or BMW) are not superior. The tear-down of these devices shows their materials cost somewhat less than half the devices retail price.
To use your metaphor, you don't get sports tyres, or built-in hand-free bluetooth, or electric leather seats in a basic Nissan model, so you can see where the cost difference with a BMW came from.
With an iPad or iPhone there is no extra functionality or higher quality components. The fruit on the back and a closed eco system is all.
It's a matter of choice, however nobody enjoys being gouged. The iPad and iPhone ranges could do with being a degree cheaper, since they've failed to innovate for some time now. The price difference between an iPhone 16GB and 64GB is especially absurd, considering the the only difference is a low-cost memory chip.
Unless Apple chose to innovate, rather than just keep pace with their competitors, then share-price drops are just the beginning. The reason I have an iPhone and not an Samsung Sx is because I don't want a glass-fronted house-brick in my pocket, so the last thing I want to see at each new release is an iPhone with a bigger screen.
If the iPhone 5C is a reality and is cheaper, then I may well purchase one, but I'm through paying twice the odds for a smart-phone for "more of the same". iOS7 is due soon, but it's more a fresh coat of paint than any kind of real change.
As for the iPad, you need firmware versions to see which one it is you're holding. Is this the "new ipad" or the "New New iPad" or "The other new old new iPad"?