I don't understand why you have a problem with this at all! Should Rick penalize himself by lowering his prices on the Gen III's for his success in designing a folder that turned out to be such a big hit? No. The quality is the same. Many makers & companies charge lower prices on new products at first only to raise them over time when they prove to be successful & popular in the marketplace. Apparently, he gets less than they are currently worth, because they sell for more on the secondary market sold by previous owners.
He's not saying that his full customs are better by charging more for them. However, they are more aesthetically pleasing in the same way that a vehicle that is fully loaded is, and so these will cost more for the "options" now. Why shouldn't he make what he wants to make??? If he wants to still produce full customs for shows because we, the customers, will happily buy them, who are you to tell him he's wrong? He's established his success with the XM-18 on hard work and creative thinking, so now he's charging a little more for the full customs. He could easily get more for them, but chooses not to. It's called CAPITALISM, and he's not being sneaky about it, nor is he forcing you to buy any more.
As has been said here already... You don't like it, don't buy it.
If & when you go to sell your Gen II XM-18, are you going to list it for the same price that you paid, assuming it isn't used, or are you going to try for current market value????
Whether you like it or not is my concern, but to slam him here for being both an excellent knifemaker and a smart businessman is well... Petty.
I'm done here. Surely someone must have contacted Rick by now, so I'll let him respond to you if he wants. I will say this. If you think that you can make as good of a product as he can, then you can charge a lower price for it and run your business any way you choose.