We tried — we really have. We’ve posted numerous articles about travel etiquette. We’ve specifically outlined all the bad behavior that you shouldn’t engage in on flights. We’ve even posted pictures that easily illustrate the dos and don’ts of proper conduct on an aircraft.

Well, people are still traipsing through aircraft in their bare feet. They’re still being inconsiderate jerks to flight attendants and fellow passengers. And they’re still forgetting that they are not on a private jet, but flying with other people.

So now we’re getting real: it’s time to start banning people from the skies. With the help of Shawn Kathleen of Passenger Shaming — a social media campaign that posts pictures of bad flyers in hopes of shaming them into minding their airborne manners — we’ve identified 12 types of people who should be banned from flying for life without possibility of parole or stand-by. Here they are. And if you’re on this list, remember: you were warned.

1. People who go barefoot on planes


(Passenger Shaming)

This is the number-one transgression on Passenger Shaming. And Shawn Kathleen, a former flight attendant, says it was this gross behavior that led her to start Passenger Shaming in the first place. “Feet — what is the deal?” she says. Once more for the seats in the back: not only are your bare feet unsightly, they often smell. And with the recirculated air on a plane, that smell can linger for a long, long time.

2. People who put their feet everywhere on planes


(Passenger Shaming)

Bare or not, your feet belong on one place: the floor (okay, you can cross them, too, but not into your seatmate’s airspace). But there are those who love putting their feet all over the plane. The worst: people who put their feet on tray tables! Um, excuse me: some of us wanna eat off of that.

3. People who interrupt emergency evacuations to get their bags


(Associated Press)

Passengers on US Airways Flight 445 from Charlotte had to evacuate upon landing in Denver, when smoke started to fill up the cabin. But a video posted on Passenger Shaming revealed a disturbing sight: despite the fact that flight attendants were screaming, “Leave your belongings!” people were actually grabbing their bags! Endangering your life and the lives of the people behind you to grab your stuff during an emergency evacuation is the ultimate in selfishness.

"God forbid a fireball comes through there and I’m still on the plane because some a-hole has to get his bag," says Shawn Kathleen. "If I survive I’m going to take him out on the tarmac!"

Turns out in this case, there was no fire," says Shawn Kathleen. “But at that moment that’s not for you to worry or decide.”

4. People who groom on the plane


(Passenger Shaming)

It’s called “personal grooming,” not “public grooming.” And yet there are people who think it’s perfectly cool to shave right there in front of everyone. “It’s disgusting,” says Shawn Kathleen. She says she understands that people on long-haul flights like to get themselves together, “but do it in the lavatory!”

5. People who groom on the plane, part II


(Passenger Shaming)

It’s not just about the guys. Let’s just say flat-out: hair removal of any sort on an airplane is a big no-no!

6. People who leave their gum everywhere


(Passenger Shaming)

If you didn’t learn in elementary school that leaving your gum everywhere — on seats, on armrests, etc. — is really bad form, there’s just no hope for you.

7. People who take off their shirts


(Passenger Shaming)

Unless you are using your shirt as a tourniquet to save someone’s life, there is no reason to strip down like this on a plane.

8. People who say “yes” to crack


(Passenger Shaming)

Okay, we’d give this guy a break for being shirtless if only he’d put on a belt.

9. People who underdress


(Passenger Shaming)

Okay, “no-shirt guy” and “butt crack guy” — we’re not mad at you anymore.

10. People who are a bit too loose with their hair


(Passenger Shaming)

Letting your hair hang over the back of your seat is annoying for multiple reasons. Not only does it cover up the monitor of the person behind you, think of what happens when meals and/or drinks are served. “Guess what: you got hair there!” Shawn Kathleen says.

11. People who use their seat as a clothesline


(People who use their seat as a clothesline)

Drying out your sexy underwear in the cabin is inappropriate on so many levels — especially when the airline you’re on is named “Virgin.”

12. People who leave their soiled diapers on the floor


(Passenger Shaming)

Do you leave your crappy diapers on the floor at home? Never mind, we don’t want to know. Just don’t do it on an airplane.

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