This is a bit tongue in cheek but also kind of interesting.

530i Base MSRP $46,800 / 3,472 lbs = $13.48 per lb.

330i Base MSRP $36,600 / 3,417 lbs = $10.71 per lb.

530i is 26% more expensive per pound than the 330i.

I was wondering why the 5 series costs so much more. The drive train is essentially the same. I know that the 5 has a lot of aluminum bits to keep the weight down. But other than that why should it cost more? Lower sales volume?