Why doesn't any of Charlie Brown's friends, from "Peanuts", just call him Charlie?

Question

I realize that he is the star, but why don't they call him only by his first name? If the answer is because Charles Schulze did it in the comic, then why did he do this? It's not as if it's out of respect, because they don't call him "Mister Charlie Brown". I was curious about this.

Answer 1

Peppermint Patty calls him "Chuck" most of the time, and her friend Marcie, who calls him "Charles" most of the time, and occasionally calls him "Chuck". His sister Sally usually calls him "Big Brother." Eudora also calls him "Charles", and a minor character named Peggy Jean in the early 1990s called him "Brownie Charles", because that's how he introduced himself.

Answer 2

Perhaps it separated him from the rest of the characters? Except of course Peppermint Patty, the only other character with 2 names and the only one to call Charlie Brown 'Chuck'. Ever notice she looked like CB with hair and freckles?

Answer 3

I'm not sure. However, if you were to call him "Charlie", then he may be mistakenly mixed up with chocolate instead of peanuts- like "Charlie and the Chocolate Factory"! Then you might have a real mess- like Recess Peanut Butter Cups! Now, you'll have to give them both credit!