I also grew up in a family where they were travelling all their lives (my mom less-so) and had a passport within months of being born. I used to have autograph books from every flight I flew as a child, and the crews would often let me help with things like picking up the headsets at the end of the flight. Until 9/11 I still visited the captain in the cockpit on every flight I took (including my honeymoon!)

As for dressing, when we were kids we always got a new 'airplane' outfit for each trip. However, it wasn't as dressy as the OP. It was a new occasion but not necessarily fancy.

These days I am totally casual. I travel a lot for business but believe comfort first (although I'm not a total slob). Jeans, t-shirt, hoody is my usual fare. As a young-ish female it's kinda fun being in biz class and people wondering how in the heck you got let in there