A lot of extra thought that goes into high-end cars. I remember reading an article about how the sound of the door shutting is carefully tweaked to make it feel substantial and expensive.

Edit: Found this: http://soundinthemachine.org/2009/01/21/the-swaying-car-door...

Few things sound like they actually do. The sounds made by technology are more a story about what it should sound like than what it actually does.

Because drivers don’t get the sensation of a “real” car in a hybrid electric car, speakers are now being placed in the cab to play synthetic engine noise for the driver. And, because it’s synthetic, the noise piped into a Prius can be made to sound like a Lamborghini.