I might wear their uniform, but only if they paid for and provided it!!
I can't see how it really matters although I know most schools carry on like this. It is extremely pretentious however to be wearing stripes until you are at least on-line. Using them during training really smacks of a "Y.T.S." mentality!
I know that a school will insist that it increases the professional attitude. I disagree with this as it depends on the individual as to how they conduct themselves and judging by the amount of flying students who happen to end up in the local or in Tesco's whilst in uniform, it's simply a poorly used way to try and get laid!
If you're are paying for your own training then wear bloody brown shoes, flip flops, trainers or jack boots. As long as your clothes are clean and not with offensive messaging then who cares?