Hello Folks. I've just been browsing here lately, but I recently read an article in the latest issue of MMIR that addresses this problem in a sense. The author was concerned about the rising costs of imported models from countries such as China, and some of the large price variations from certain companies. After getting a chance to talk with people from these companies, he developed a pretty good perspective on the issue.
Apparently, the price change represents a change in the way Chinese companies are trying to service the model making community. The model making hobby is largely driven by new content, since old kits sometimes suck, or become unavailable, or just simply due to people not wanting to remake the same model a thousand times. Research and development for new kits is an expensive process, and it was a very slow process when Chinese companies were making large quantities of each kit, and selling them at a low price.
With the international market (everyone but China themselves) being the primary consumer of these models, the decision was made to produce fewer numbers of each model kit, and sell them at a higher price to their primary consumers (since we can actually afford to spend a bit more). This allows them to get back their money sooner, and put it back into research and development for new kits sooner.
Also, apparently model making is still not a very popular hobby in China, and this practice also allows them to keep the prices lower in China, in an attempt to try and increase the popularity of this hobby.
The full article is in the latest issue of MMIR 62 (Military Miniatures In Review, and the author explains everything better than I did here.