When the teacher has to take away from instructional time to address the dress code violation then all the kids suffer. As for cost. I don't know how it could cost that much more for your child to have a uniform.
The Rotary Club, The Assistance League, and our school's PTA are three such groups. Our school also has a uniform swap at the end of the year, where parents can swap out uniforms their children have outgrown with other parents. They are a burden to the less fortunate families, the coat of uniforms is really expensive. Personal experience has made me realize that because when I was in school I had to wear a Polo everyday they are extremely expensive and they are hard to find cheap. There are also ways if a family is in dire straits that the school can also help out financially. There are so many options available. School uniforms are important because they help to promote safety at schools (especially in gang areas they fit better, and they're free of distractions. Public school uniforms are often khaki or blue bottoms and a solid color polo shirt. Often times, uniforms can be purchased for less money than regular school clothes. Wal-Mart and Target have uniforms for purchase at incredibly low prices.
Uniforms set a standard for the children and make the community look a lot better. School uniforms are not less expensive then regular d they keep people from expressing their creativity. Oftentimes, the school will lend financial aid in purchasing uniforms. Finally, uniforms aren't even a problem for poor people, cuz screw poor people. School Uniforms are Almost a Necessity, in these times where there are children killing themselves because of bullying, children having babies as young as fourteen and parents who are unable to be home to monitor what's going.