Wearing uniform represents unity in that community. It is the symbol of where you belong. For college student, it's important to wear uniform to create sense of unity and pride .Also, wearing uniform reduces discrimination between students who come from different social classes. No braging about brandname outfits, everybody is equal under the same uniform.
Some people also believe that wearing uniform tend to make the students focus less about fashion or what they would put on each morning and focus more on studying.