Re: Airport/Travel Outfit and Makeup and Hair.?
Don’t worry I’m a bit of a snob like that as well 
I don’t wear sweat pants, and if I had to, I would not change into other clothes in those washrooms especially on a long flight. Wear cargo pants! They are perfect. You can get cropped ones too, pair it up with a comfy top and carry a cardigan, hoody or a trench coat if you like.
In case you don’t know what cargo pants are:
http://oldnavy.gap.com/Asset_Archive/ONWeb/Assets/Product/633/633367/main/on633367-00p01v01.jpg