[Rata]

I'm not so sure cost has anything to do with it. And hopefully MS without sounding like I'm poo-pooing what you're trying to say, I'm also pretty sure 'perceived value' is not the issue. If a product is considered good and earns a reputation as such I seriously don't think selling it 'too cheaply' is gonna put people off buying it. Aaron Murphy's stuff (considering the larger scales he does) is of VERY high quality and exceptional value. Try and buy a plastic in his scales for the same price. I doubt Aaron; or any other designer for that matter; is gonna improve sales by charging more.
I don't know what the reason is for the lack of interest is, but if I was to hazard a guess I would say shear volume of choices of models (compared to plastics) available to a limited and finite buying market. Most designers offer multiple-often over 10- variants of each subject, and then you've got repaints and so it goes. I'm certainly not complaining about this because to me this is one of the best aspects of paper modelling but the literally (again compared to plastics) thousands of choices available has got to mean a thinner slice of the pie. We would all love to see this hobby take off and be embraced by the masses and sites like this certainly promotes doing that as well as any other similar site, but sadly as with the downturn of the popularity of plastic modelling last century there are too many 'quick thrill' pursuits that attract potential enthusiasts away.
I hate the thought that a good bloke like Aaron Murphy is faced with something like this, but I don't think any individual; least of all another designer; is at fault here.
Just my 2 cents.