Demand. It's ubiquitous. I've seen it in every prototype or mockup or early version of every larger-than-a-breadbox system I've worked on. It's used for lighting, sound systems, camera mounts, even shelving in some cases.

Whenever two or more engineers get together to design something, 80/20 is there in spirit at least.

By that logic, the lego sets we buy for our kids should also be the cost of plastic ;)

You used to be able to buy a basic extrusion die in China for $500 and off to the races at $0.80/lbs extrusion cost with 500kg MOQ.

Wonder if there's patent protection on the US sale of that profile?

You still have to cut it, ship it, distribute it, sell it. If you were buying 500 kg, you too could probably find a way to get it cheaply made.

As a counterexample, I will say:

The cost of typing characters on a keyboard is nearly zero. So why is software still so expensive??

Remember it isn't quite a basic extrusion die because it has a hollow in the middle. I assume that at least requires some fancy 3d shape.

The patent expired in 2013. (US5429438A)

I wonder if just nobody noticed?

I imagine most users are engineers employed by companies. This would tend to decrease the price sensitivity while increasing the desire to go with a brand name.

I see now McMaster-Carr has their own knockoff, they for sure can successfully leverage their reach, reputation and brand recognition to compete. I imagine price must go down once enough people catch on that this is a relatively unprotected commodity and enough reputable players have cross compatible offerings.

https://www.mcmaster.com/products/t-slotted-extrusions

> So why is that stuff still so expensive??

Bosch Rexroth.

Bosch's extrusion profiles are what people at big co's who need stiffness and don't care about price tag will buy.

My guess is that Bosch warps the whole market up and the competion follows.