First and foremost BMW in the US is a luxury brand -- so expect to pay a premium compared to other brands. The Japanese brands don't have the same cache and reputation that BMW & Mercedes have so they have to undercut them on price and features. I don't understand why it's still such a surprise to people that BMW's are more expensive than comparable Lexus's. Yes, Lexus has come a long way since its inception but to many, it's not on the same level and that will dictate market prices.
There are buyers that aren't willing to pay BMW prices so they go with something more affordable. Nothing wrong with that. For me, I'm willing to pay the BMW premium for driving dynamics and sheer thrill. All the added features are just a bonus and wouldn't have changed my buying decision.