Dirk-
Certainly there are a number of asuumptions on both sides -- and a leap of faith. Faith that I do not seem to have.
First, I do not prefer Leica. I do not have any Leica equipment and never have. Most of my equipment is Contax -- A fairly complete G-system, and a 645 system, and I used to have a few of the 35mm MF cameras (still have a few lenses lying around). The only break from this is a Canham 4x5 and a Toyo 4x5 (I even have a Zeiss lens for them), a Voightlander Bessa L with that nifty 15mm Ultra wide Heliar (a bargain), and a Olympus E-20N with a bunch of accessories (still waiting for a viable ND). I view the high prices paid for limited Leicas with different finishes as fanatical, irrational, and a way to relieve a little money from people with much too much of it. They make a good, if expensive, product normally, that suits a particular type of photographer. I don't think it particularly suits me, which is why I do not own them -- contrary to your assumption. By the way, in terms of longevity I was refering to the traditional mechanical Leica, not Leica digital. Interestingly, the Panasonic badged version of these Panasonic made camera even get to claim the "Leica" name on the lens -- making it clear that there are no differences between the cameras other than name -- and, of course, the higher price on the Leica badged one.
Second, there certainly seem to be divergences in what people see as value. Perhaps I am much too practical in nature, but merely slapping an extra logo on a camera does not increase its value for me. It still performs as it did without the logo. That said, I do not think it is a bad idea. These things are often done from a promotional point of view, and it is a nice thing to do for a group that supports you. I just don't see why one would pay a significant premium for it.
Finally, regarding the Kyocera/Contax twin SL300R cameras. Kyocera certainly did not go out of its way to differentiate the Contax version from the Kyocera. They may have changed the color. But they didn't even bother to give it a different model number!! This along with the same specs, logically leads one to question whether they are the same. I do not take it on faith that the Contax must be superior because it is called a Contax. Is the premium for the Contax over the Kyocera as ludicruious as the premium for the Leica over the Panasonic? It seems to me that a test of the cameras is a rational way to resolve this. I learned long ago that you can not take these things on "faith".