Customer feedback
Speaking as a previous customer, I gained the impression that the uniform was for the benefit of the instructor, to differentiate himself from the 'punters', to let the student know who's boss. Most of the experienced instructors I flew with preferred casual wear. The little Hitlers strutted about with their shiney shoes, shoulder braids, and ties, grasping their clipboards. I'm not saying every uniformed instructor fitted this description, far from it. This was the impression it gave me. I chose not to fly with them. Our school let the instructors wear what they wanted, only one instructor did the stiff shirt and tie routine. I believe in my case the pilot student relationship was not helped by the uniform. I preferred to sit next to someone dressed as I was, rather than one that looked like a policeman. I don't share the belief that the only tidy clean attire is a white/blue shirt with tie, black/dark blue trousers and shiney black shoes. But this is only my point of view.
So I suppose I agree with nonradio, from the customers perspective
CC