I am in agreement with the assessment of your character, Stephen. Although you are not obligated to help new guys, if you choose not to help you should keep your mouth shut.
If anything, your wish for a "noob marker" might bear some small merit to indicate a 2-weeker on his free trial, but not for anyone who is a paying member (noob or not). Identifying a 2-weeker will at least let people know that they are inexperienced and might need some extra help when you tell them to bring troops or to kill the ords or VH, since they might not know where the maproom is or what it looks like, etc.
I'm all for helping the new guys...I used to be one.