Message when running yum update

[JD]

# yum -y update
Loaded plugins: auto-update-debuginfo, downloadonly, etckeeper, 
langpacks, presto, priorities, product-id, refresh-packagekit,
               : subscription-manager
Updating certificate-based repositories.
Unable to read consumer identity

This machine has not been registered and therefore has
no access to security and other critical updates. Please
register using subscription-manager.
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This is the first time I see the registration thing.
Why is this being done?
Why does anyone have to register their machine?
I see no reason for this other than monitoring people's machines.
This is totally unacceptable.