The difference in value between AR and VR has been a hotly debated topic for several years now. Most people, however, try to spin this debate towards only one specific thing, which is usually gaming.
AR lets you see the real world and the CG world, VR only the CG world. Either way, the important thing is that all images are stereoscopic, as this is what allows for immersion and realism. The very definition of VR is a simulation of reality, which is not possible without stereoscopy. The real world is stereoscopic, so AR should also be stereoscopic so that the CG image matches the real world image. Only then does AR approach the quality and realism of VR.