We don’t fly much but we’ve started wearing loose cargo pants for the comfort and the pockets. I like to have my phone, which has an attached pocket with credit cards securely on me in a buttoned pocket. I wear a loose blouse or polo shirt and always a sweatshirt in case it’s cold or, as on one overnight flight, to cover my nose as the young man in a hoodie sitting next to me slept with his head on his tray and farted throughout the night.
And tying in with plane snacks, after a national parks vacation last year my husband felt he needed to carry on all our uneaten snacks so at TSA he removed granola bars and other things from upper pockets and a huge bag of trail mix that he’d stuffed into one of the lower pockets. Much to the amusement (thankfully) of the TSA agent who said “you’ve got ALL the snacks!”