I found this quote interesting, it was made by reddit user /u/Bytewave, he is a Senior Engineer in a well positioned Telco in Canada. He posts his stories and experiences to reddit.
I often found a hell of a lot of Passive-Agressive CCing and I find that his opinion is relevant.
“Passive-aggressive CCing (where you copy ‘important people’ who do not need to be involved in an issue to throw weight around) is one of the surest giveaways that someone is not a reliable professional and should not be trusted with anything critical. Sometimes you may get a little more attention to your issue because of it, but you’ll never be respected if you work that way. It’s not limited to IT either, it’s pretty widespread unprofessional behavior. Asking for another tech’s opinion if you think you got wrong answers is fine, but the moment you’re obviously playing the hierarchy – people remember that. Of course it’s different if it’s obvious that an issue needs to be handled by management, but if you believe that’s the case, make it the subject of what you’re writing, not a CC.” – /u/Bytewave