I think I'm answering my own question here.

Is there any reason other than than the free market to explain why similar commodity track components can vary in price between sizes? I'm thinking specifically of the crankset prices on Business Cycles...I can't think of any other reason why cranks in 165 should ever cost more than the 170 size. I mean, there's LESS crank. Any thoughts?

Also, is the forging process the reason why a track stem costs much more than track handlebars? After all, Nitto can fit a whole hell of a lot more stems in a box from Japan than they can B123s.

yeah forging is more expensive then extruding, hence stems that are forged not cast cost more then handlebars that are extruded and rolled

Additionally, dies for stamping cranks cost a hell of a lot. Over a million bucks. So if you are using the same dies (modified) for track and road, such as would be possible for 170 cranks, you could distribute that die cost over more cranks, meaning it would cost less to manufacture. In the case of 165 cranks, they need smaller dies for a smaller run, meaning the tooling cost is higher per crankset.

Ah, I didn't think of that.

Actually, in the words of AdamKell "Call John. I'm sure he'd love to talk your ear off about it."

tooling for forging is really expensive.
demand for track stems is relatively low. much lower than say, the technomic road stem.
thus track stems cost more.
(yes, this is way simplistic and there are other factors that i'm overlooking)

the crank price difference is probably also due to supply and demand (though only the campy cranks seem to be more expensive in 165 length - maybe they're running low on stock)

Ah, it all makes sense.

I know I've seen differences in the prices for Sugino 75s according to length on sites other than BC---which could also be the supply factor.