Mine definitely do the same thing! I have no clue how to sleep w/curls and keep them looking the same.. I have to wet them every time.. I've only been lucky ONCE w/sleeping w/a pineapple and styling the next day w/a lil gel.. but they still look slept on..
I've been told that buns really help growth, kinda just letting your hair do what it does... I'd believe that for the roots, but the ends/where the scrunchie is around it? Not so sure...