People who have to make a big deal that it is their first flight....especially when they are over the age of 12.

When the person is sitting next to me and says "this is my first time on a plane" I usually respond with "I've already done 20 flights this year and it's only February." I know, I'm mean, but if I don't stop it there, they must tell every single person who walks by that it is their first time on a plane.