From Netorama:

This year lawns were placed in both the Mann and Olin libraries, as well as three other locations around campus, as part of the Cognitive Restoration initiative. The project is based on Attention Restoration Theory, which says that direct exposure to nature, viewing nature through windows, and even viewing images of nature are restorative

Who wouldn't want to go to a college basketball game where everyone dressed up in outrageous costumes and sang Christmas carols?