The cost of pushing aluminium through an extrusion die is nearly zero. The die cost isn't much anymore in the world of cheap CNC machining. And the R&D costs for coming up with the shape shouldn't be high (and already paid off years ago).
So why is that stuff still so expensive??
Whenever two or more engineers get together to design something, 80/20 is there in spirit at least.
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??
I wonder if just nobody noticed?
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.
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.