Ah, say you have a younger, immature sibling who gets mad at you for taking 'his' cookie so he creates an account, fucks around on purpose, and gets you I.P banned? You can't always be around to make sure that kinda shit doesn't happen, especially with younger siblings who don't fully appreciate following rules nor how major a violation and big of a deal they created. Yet, some people could blame imaginary siblings for a mistake they made and abuse the system with other accounts.
A very tricky situation indeed :O