You’ve probably already read the stories about people getting kicked off of planes or denied boarding for wardrobe malfunctions.  There was the burlesque dancer who goes by Maggie McMuffin, evicted from a Jetblue flight between Boston and Seattle for wearing short shorts that were too short; Green Day guitarist Billie Joe Armstrong ejected from a Southwest flight when he declined to pull up his pants; a Southwest passenger booted off for showing too much cleavage, and an American flier kicked off for wearing a T-shirt emblazoned with a four-letter word.

In a recent Airfarewatchdog poll, 59% of over 2000 respondents opined that airlines have a right to refuse to carry “inappropriately dressed” passengers.

But what many don’t realize is that it goes both ways: the better you’re dressed, the better an airline might treat you.

Last week I had dinner with Susan Andrews, a real estate agent in Los Angeles, who recounted her recent flight on British Airways from London to LA.

Knowing that I write about airlines, soon after we sat down at Norah, a new West Hollywood dining spot, she asked, “Oh, I was wondering if you could explain this. I was upgraded to first class! I didn’t ask why. I’d never flown in first on BA and it was amazing!”

I asked if she had “status” in the airline’s frequent flier program. As I suspected, she didn't (too busy selling real estate to travel much). Just a regular customer (the lowest “Blue” level in their Avios program, same as me, by the way).

Looking at her across the table and how she was dressed (and realizing how she always dresses), I already knew the answer; but I asked anyway, “Okay, what were you wearing? Were you dressed like you are right now?” Other diners were in the usual SoCal T-shirts and sneakers, the same garb that most people fly in these days, but Susan was wearing a stylish cream colored knit dress. 

"I was wearing something similar," she answered. "As I was boarding the agent handed me a new boarding pass. I had no idea it was in first and got lost finding my seat” on the double decked Airbus A380 that plies the route. 

So what happened?

When a flight is oversold and airline personnel have to move people up a cabin or two, they usually upgrade passengers with status. But, what people don’t understand, or refuse to believe, is that after those passengers are taken care of, if a gate agent needs one more passenger, they’re not going to upgrade the person in flip flops and short shorts.

It's in their DNA. Airline employees, when traveling on a free “pass,” must adhere to a strict dress code. I once worked for Eastern Air Lines (remember them?) and showed up at a ticket counter wearing a nice navy blue suit but no tie while traveling on a pass. Although we employees usually flew in first class if seats were available, the agent took one look at me and handed me a seat in the back of the plane. When I asked why, he snarled (and I quote): "The way you're dressed you don't even deserve to fly at all!" That was in 1988 and something I'll never forget. Which is probably why I dress up when I fly (yes, that's me in the photo, lounging in a British Airways first class sleeper seat. In a nice navy blue suit. But no tie).

So yes, airline employees resent upgrading (or even flying with) people who dress like slobs. And while it doesn’t happen often, you can be upgraded for dressing respectfully. It happened to me once on United, where I had no status, and was the only one on the flight wearing a suit (and a tie).

And you can get downgraded, right off the plane, for going the other direction.

And you know what? Even if you never get upgraded, you'll at least get some compliments.

Follow me and my team on Twitter @airfarewatchdog