My boyfriends niece is 5 years old and her parents still let her use a pacifier! Aren't they wrong for this?

Her teeth have this permanent shape of a pacifier in them and it looks horrible. She also still sleeps with them in their bed. She has an older brother who is almost 8 and he doesn't have the same babyish habits. She cries at night if she can't have her pacifier and they still give it to her. They have tried giving her pacifiers to the "paci fairy" who takes her pacifiers to little babies who need them but she gave up all but her favorite 3. How can they get this behavior to stop? It's obviously them giving in to her and she's in charge here but it's got to stop! She can't start kindergarten and still use a pacifier at night!