Why are the lenses which are in a kit with DSLRs generally low quality lenses, or at least rarely match the quality of the DSLR body?
For example, a new Nikon D7000 ($1100) comes in a kit ($1300) with a 18-105mm lens. Even if this lens can be great for general usage on a Nikon D3100, it is obviously strange to see a $275 lens on a $1100 body.
It means that:
semi-professional photographers who will buy a D7000 - 18-105mm kit will need to replace the lens by a much more expensive 18-200mm VR2, or, if quality matters, a 24-120mm with, if needed, a wide-angle lens and telephoto lens.
non-professional photographers who will spend more money for a D7000 - 18-105mm kit will not gain too much comparing to cheaper DSLRs with a separate 18-105mm lens.
So, what am I missing?