Could be just that but I have flown frequently at Christmas time and have never seen uniforms fill more than 20% of a plane.  What is the rule about when you can wear a uniform and when you can't.My Brother was military and he only wore his uniform whenhe was required to and traveling in uniforms required when traveling to a duty station but not when off duty and travelling to relatives. Here's the military code rules: https://www.armystudyguide.com/content/Prep_For_Basic_Training/Prep_for_basic_uniforms/when-the-wear-of-the-army.shtml It becomes optional for travel to see family.