In my opinion, it's a throwback to when airlines sponsored students at the likes of OAT etc. Which in itself probably relates to the naval tradition and the merchant marine, which is where aviation took it's cues from in the early days. The excuse that the wearing of a uniform encourages a sense of professionalism etc is total beeolucks. If you need a uniform for that you are screwed from the start.
The reality is that it's all about corporate identity and is a public relations exercise for potential customers. Almost all flight schools have some sort of uniform for their instructors. Quite rightly, it does give an air of professionalism. Uniforms are OK, most companies that deal with public, shops, bars, restaurants have a uniform of sorts. None of them expect their customers to dress in a uniform.
So why do flight schools? I think it's just a bit of a tradition, a tradition that needs to pass into history. As for issuing bars and stars and wings and things, well pulleezze.
