Have you ever gone to a restaurant because they changed their logo? Why do they do it then?
It isn't that they make a choice about a school by the uniform. It affects the subconscious impression of the school.
Is the school old and dull or fresh and lit (or whatever means "cool" these days)?
I doubt most students are aware it is even somewhat influencing their opinions. It's just something that's there.
I don't think they are critical to success, but if they make the current players happy, create a positive impression of the school and don't do anything to tarnish the U's reputation then what is the downside?
Though admittedly, everyone knows that kids pick schools based on academics, the number of Fortune 500 companies in the area...