Why does Nikon prefer Electronic VR?

Why does Nikon makes few cameras with Optical Image Stabilizer? I think O. I.S is better than the digital right?

Added (1). @freeman: well I said Electronic VR not "Optical VR" you know.

VR is an optical stabilizer. Read the page.

http://imaging.nikon.com/...rosite/vr/

To give the image more stablity

Isn't that the same thing? Nikon's VR IS an Optical Image Stabilizer system.

Are you confusing OIS (which is built-in the lens) with Mechanical Image Stabilization (which is in the camera body itself)?