I loooove flying with my Skechers... easy to slip on & off at security, and very comfy to wear if you end up walking or standing for long periods. There are tons of styles to choose from and you can find them between $30-$60

My fave styles:
more casual/athletic Point Blank or Riches

I have these in a few colors, and they work with dressier "work" outfits: Step Ups or Engage/Cage