I don't agree with the implication that high prices (for antique or vintage catalogs, tools, machines, etc) are completely artificial - i.e., exclusively a function of appeal to a wealthy ego.
Collectible catalogs have "going rates" just like collectible tools, formed dynamically over time as exchanges occur between sellers and buyers, and it's a function of desire and availability (rarity). You can absolutely track those "going rates" or "informed market values", passively (following eBay auctions and sales), or actively (participating in auctions and sales).
Heck, Worthpoint's name and entire business model - to collect auction and sales data for an item and present it in list form by date and price - is built on tracking a thing's worth. Sure, there are spikes, and they are usually the result of someone consciously paying "too much" just because he wants to and can. But that doesn't mean that the "too much" price always becomes the new going rate, although, if it starts a trend, it can.
I'll give you an example from my niche.
I am a WWII picker. I buy for my own collections, but I also buy to sell, mainly extras, and mainly to fund more collecting. I don't shop or sell on eBay. I troll estate sales and flea markets - because they're usually uninformed sellers. And I sell in "club" environments on esoteric websites where WWII guys gather. Primarily tools, and primarily on-board vehicle toolkit tools. Guys with restored or preserved Willys MB jeeps like to have the accessories, such as the tools, as much as guys with Model T's or Packards, etc.
This is a great example of a very informed market. Serious sellers and buyers knowing, generally, what everything is worth, like water finding its level resting place.
A correct screwdriver can go for as high as $100 right now. Correct tire pumps at least $100 depending on condition. A complete set of five DOE wrenches runs about $200 to $300 depending on brand. The smallest wrench (an ISN 723) can be as much as $125 by itself, again, depending on brand. Rarer items - such as the wheel puller or tire chains, much, much more. I once sold a brake bleeder wrench, no bigger than your little pinky, made of pressed steel, for $700. Those prices are not artificially inflated, and they're not a function of bragging rights - though plenty of bragging is certainly done. They're a function of desire and availability (rarity).
I'm not a catalog collector, per se, but I've been watching vintage (1930's and 40's) catalogs for awhile, mainly from automotive tool makers. I don't know much about other catalogs (machinery, specialty tools, etc), and even less about antique era (late 1800's to 1920) catalogs for tools or machinery, etc. But I'd bet there are informed market values, just like there are for tools or knives, etc, EDIT: and I'd bet the Pricing Guides Mark Donnelly is also selling on eBay include that kind of information. EDIT 2: I still think some of his prices are high. As I said, if he gets $400+ for those Mossberg, Atha, and G-P cats, I'll eat crow - and immediately adjust my own catalog prices accordingly.