My observations:
1. There is the psychology of the auction that enters the picture, where bidding becomes a matter of principle.
2. We have all seen the large collections in the media, items on display to admire. We boomers will die off and those large, unrun collections will be put on the market, competing against each other, which will lower the prices.
3. Look at the new generation of millennials and those following. Will they sustain demand we see in some instances now, similar to the boomers? Not likely, since their collective experiences are different from today's buyers. A major difference: Joshua Cowan was careful to develop the market with restrictive choices, creating a thirst for more. I am that way with the 200 series of Alco's. I recall coming of age with the 1958 catalog and realizing there are desirable variations. Today, by contrast, there are many more choices and variations, thus reducing the desire for those earlier, particular variations.
Mark