Anonymous letters are common in my mailbag. One arrives every few days, many of them handwritten. Some are well-thought-out with very neat penmanship. Others are scribbled, obviously in anger or haste. Maybe both.
We don't publish nameless letters, but I read them nonetheless. Some are so profanity-laced they'd make a sailor blush in shame. Others are thoughtful and could otherwise be published unedited, had they come with the authors' name.