But it put me in mind of my favorite (and, well, only) Leapday

If you have a birthday on leap year, your 21st never falls on the date of your "real birthday", it falls the year after you "turn five". (And, as we found out in an unrelated tale, the state has decided that means you're legal to drink on March 1st and not before.)
This one time, I took my leapday buddy to the store to buy beer, but elected to stay in the car for some reason. This is the bad_service that was related to me when she came back like twenty minutes later with beer.
Me: all things awesome
LYB : leap year baby
Me: Dude. What took you so long?
LYB: You will not F-in believe what just happened to me.
Me: What?
LYB: I went in there to buy beer and show her my ID...
Me: Oh, is it expired? (she didn't drive at the time so this was a real possibility)
LYB: No, dude, she said February 29th wasn't real and that my ID was fake and tried to confiscate my ID!
Me: What?
LYB: She got all pissy and said "Yew must think I'm steeeeewpid. There ain't no February 29th. There's 28 days in February." (We are all Southern, she just intensified her accent here.)
Me: You are f-ing kidding me.
LYB: I asked her if she had ever heard of leap year and she just stared, I swear to God.
Me: You are lying. (I am dying laughing)
LYB: Just then someone came up to the drive-thru and she asked them all pissed off if they had ever heard of February having 29 days and they stared at her like she was an idiot and were like, "Yes" and then told her to check that it was an even year on my license.
At least someone knew how to do her job. Seriously, how does one get to the age of 21 (which is how old you have to be employed at that convenience store) without knowing what leap year is?