College paraphernalia from other schools?

Why do people wear shirts, hats, sweatshirts, etc. from other schools which they do not attend? I constantly see students on campus repping Vanderbilt, USC and UT. It blows my mind. Reality check- You go to SMU. It is sad that our campus cannot even support its own school. No wonder only about 20 people attend the sports games. Come on SMU, have a little more pride.