International ISO regulations?

Question

ISO

I asked myself the question: according to what regulatory documents "ISO" - large telecommunications companies produce equipment for Internet networks.
What was my surprise when I discovered that you have to pay for such information.
Since I have never been in the “topic” of ISO standards, this is very strange for me.
It turns out that to satisfy my interest - I have to say goodbye to more than one hundred euros for documents ranging from 8 to 100 pages.
This is fine?
Do you really have to pay for this?
Somewhere the price is 10 euros, and somewhere 50 euros for the same thing.
Who has experience - tell me please.

Answer 1

You will be surprised, but you also have to pay for GOSTs.

Answer 2

And what is wrong?
Is it written somewhere that ISO documents are in the public domain?