So this begs the question.
What if I bought one of these cases and stuck in some cheap class D amp inside and sold it to some unknowing person, would they be able to tell the difference from the original?

A lot of people only buy the big high end stuff because it is expensive, and quite honestly don't even know what good sounding stuff sounds like.

How much they spent is the only thing that matters to them. And it is always more than YOU spent!

They are "Flexing" to the unwashed!

I’m taking this as they are selling only the cases.  I’m not thinking that they are selling the “guts”.

Not a scam.  Simply that in China the working class can't afford a Gryphon Amplifier, or an Accuphase preamp but they are nevertheless audiophiles like the rest of us so there is a large market for copycat amplifiers.  

The number of empty chassis that I posted demonstrate the demand.  And these are the actual prices of the chassis you can buy on Aliexpress right now.  In addition to these empty chassis that anyone can purchase, they also have completed working copies of most likely every single unit pictured.

There is within this audiophile market in China not only near perfect fakes, but many have been 'upgraded' with improvements on the original designs so they not only get to have feel and look of a name brand amplifier that they normally couldn't afford, but some have the last laugh because they also sound better.  They don't want the originals over there.  

So, the point is when you see amplifiers listed used somewhere don't automatically assume it's the real thing.

Some of those are pretty cool ! If you're a hobbyist builder and want a "finished look" for your project you couldnt buy or have anything machined like that for those prices here in the states . Not from a trick you dishonest angle but for personal projects those are amazing.

If it weren't such a hassle to pot a tranny Id totally toss  rounded corner transformer covers on my Decware pieces .