I use CC quite a lot. People in the CC are supposed to read the email because it is in their interest, even though they don’t need to reply.
E.g.
To: Graphic Designer
Cc: Programmer, Middle Manager
We considered the three options that you gave us. We decided to go with option 2 because option 1 was too technically complicated to implement and the big boss didn’t like the color of option 3. Please, send the assets to Programmer and forward your invoice to Middle Manager.
Eh, I see it as more of a “if you come across a need for this information, it is searchable to you, but response is not expected.”
I use CC quite a lot. People in the CC are supposed to read the email because it is in their interest, even though they don’t need to reply.
E.g.