http://www.bin-store.com/blog

The other reason for dorm room bins is easy transportation. You will only be spending about 6 months of your life in your dorm room each year. During summer and winter break you’ll be moving stuff out of your dorm room—during summer everything has to go. Bins make it easier to transport your things, and plastic is lightweight, which makes it easier to carry stuff. It takes hours to move in or out of a dorm room, and it definitely makes the task less of a burden if you are also more or less moved in once you get your stuff out of your car and into the dorm room. If you use bins for storage, you don’t have to unpack everything—just find places to keep your bins!