^^^ I agree; it's a pretty subjective assessment. But even if there was some objectively measureable "sound quality", I don't know why you would expect it to be linearly related to cost. I think for most products, the improvements become increasingly incremental as you get higher up the price scale.
Plus there are a number of other things you might factor into value, such as build quality, customer service, available accessories, even name brand appeal. Maybe there is another mic, for say $500, that somebody thinks sounds exactly as good as a Schoeps. That person could well decide that the cost difference is the most important factor and go with the cheaper mic. Or they might decide that the quality, excellent customer service, and enormous flexibility (in terms of mounting, powering, other capsules, etc.) of the Schoeps was worth the extra cash...