Earlier quoted context omitted.
While no one wants anyone to steal a car, almost no one would mind freely cloning a car. The trouble truly is that 3d-printing hasn't gotten that good yet.
The car would be unlikely to exist if its maker had to expect free clones without compensation. So yes, people would mind.
It makes perfect sense to me that the big carmakers could get together some day and develop a handful of car platforms that all their cars will be built upon. That way they can buy the parts from any number of manufacturers (on-demand!) and save themselves a ton of money.
They kind of already do that, actually =)