What are you wearing?

Some martial arts schools wear uniforms, others don’t. Sometimes the uniform is very specific (it must be purchased from the school), other times it’s more general (you can wear any color Gi, but you have to wear a Gi). What’s the deal? What does a uniform accomplish?
Well, it can be a source of revenue for the school. I think a lot of people harp on this as a real strike against strict uniform policies, and I’m sure there are some schools out there who are fleecing their students and making a ton of money off uniforms. It’s something to look out for, no doubt.
On the positive side, I think uniforms help put students in the right mind frame. You put on the same thing every time you train. It’s a ritual. It reminds you of what your role is, what you’re working on. I know for me, putting on my uniform helps me set aside whatever else is going on in my life and to put my mind, body, and spirit into the joy of training martial arts.