if my instructor turned up for work looking like he just got out of bed I would question the quality of the product
NO ONE is saying that they would look scrubby.... wearing a shirt and tie does not necessarily mean clean and NOT wearing a shirt and tie doesn't mean looking like something the cat dragged in.
Thirdly most of us are looking for an airline job and we will all have to wear a uniform then.
that, too, is not true. There are many instructors out there that do it just for the joy of instructing, often holding down other full-time jobs. I experienced many hour-building instructors and I didn't like their approach (sorry if I generalise here... and THAT would be something for a new thread I think). They didn't care much for the needs of the student, they only wanted to build hours.....
What you wear does NOT show whether you are good or professional or not.
My humble opinion.
Westy