Why do people play classical music to their babies while pregnant?

Some parents believe in the Mozart effect, where babies appear to be smarter after being exposed to classical music. However, studies have debunked this theory. There are still benefits of listening to classical music though! It helps to calm and regulate your mood. http://www.babycenter.com/0_the-mozart-effect-classical-music-and-your-babys-brain_9308.bc