Originally Posted by Pharmacist

i would think if it was a cost issue, the opposite would be true, it would be one piece bonded to the bumper. i believe it is actually more expensive to manufacture all the extra clips, tabs, and bolts to make it removable. either nissan has it there as an option for tuners to add cooling ducts or forced induction, or possibly they have it there for themselves in case they decide later on that the z will become turbocharged. i'll try and email nissan north america and see what they say.