Why?

Madalyn is 3 and true to her age loves to ask me "Why?" questions a lot, a whole lot.
The other day she asked me why we have ears. I told her it was so we could hear sounds, like music and talking. She looked up at me and said "No, it's so we can stick our hair in our ears." Madalyn has had an obsession about putting the ends of people's hair in her ear and tickling the inside of her ear with it since she was a tiny baby. It used to be anyone's would do but now she just sticks with her own ponytails. She gets frustrated if I do a hairdo that doesn't allow her to do this. I am fine with her sticking it in her own ears, but it creeps me out when she does it in mine.