NEW YORK (MainStreet) — What is a fair price for a bottle of water? Question two: do only suckers shop at airports?

The questions are intertwined, because there now is a loud - and ugly - lawsuit between the upscale retailer Kitson and the Hudson Group, an operator of some 700 stores around the U.S. including its Hudson News, the largest newsstand brand at airports.

Ground zero for this slugfest is Los Angeles International Airport (LAX), where Hudson Group operates two stores under the Kitson name. The relationship blew up when Kitson took its Smartwater - typically priced around Los Angeles at $2.55 for a liter, according to Kitson - to Hudson and asked to see it on the shelves of its airport stores. Hudson declined. A brawl ensued, with Kitson alleging that Hudson just wants to rip off parched travelers with other more expensive water.

Understand that the trigger for this fight are TSA rules that effectively prohibit carrying a full bottle of water through security. But many passengers get thirsty in the low humidity environment of a plane, so it sets up a captive market to come prepared with water, at essentially any price.

There is a way to beat this system, told to Mainstreet by a frequent - and frugal - flyer. Read to the bottom to find out how cheapskates stay hydrated without breaking their budget.

First, back to the Kitson - Hudson slugfest: Hudson naturally has a different take on the situation. Attorney Brian Timmons said, “Kitson has no real history of selling water in its stores. Kitson is known for selling pricey items in its high end boutiques. So anyone who thinks that Kitson is really motivated here by an altruistic concern over the price of water at LAX has either never shopped at a Kitson store or is really naïve.”

Timmons’s claim - Kitson simply wants to break the deal with Hudson that lets Hudson operate the LAX stores with a license to use the Kitson name.

Kitson spokesperson Brad Chase snorted at Hudson’s claims, and he tossed out the zinger that at LAX a contract stipulates that merchandise cannot be marked more than 18% over typical street value and, by Kitson’s math, Hudson is marking up water 100%, usually charging around $5 for a liter.

Timmons disputed that, too, saying that at some LAX locations, Hudson charges as little as $2.69 for a bottle of water.

That fight will have its day in court, but for now it has shined a glaring light at a tough question: do only suckers shop at airport stores?

Note: some items are sold at the marked price such as newspapers and magazines. There is no reason not to buy them at LAX, EWR, wherever.

There also is the matter of food, and if you have a long layover - or simply a long flight ahead of you - eat in the airport. It will cost more than you’d pay downtown, but it won’t cost more than the airline will charge for inflight meals. Of course, almost always, airport food tastes better.

As for the rest - everything from aspirin to a bag of nuts and maybe even a bottle of water - you have to know you are overpaying. And if you do and you buy it, don’t whine.

But still -- despite knowing the markups - we buy at airports. There may even be good reasons.

Louis Altman, CEO of satellite phone company GlobaFone, related that he recently got off a plane at Heathrow, to pick up a flight to India. He realized he had left his Bose noise cancelling headphones on the London flight and, said Altman, “I am addicted to them.” When they couldn’t be found he marched into an airport shop and plunked down $40 more than they should have been but, said Altman, with a long flight looming it was money well spent on a new pair.

Marketing strategist Rachel Weingarten even suggested that sometimes the smart thing just is to embrace the absurdity of airport prices. She said: “when stuck at the airport in Ireland some years ago I overspent considerably on a flat cap. Everyone compliments me when I wear that particular chapeau. Sure it cost a small fortune, but it allowed me to be free with money and silly and just enjoy an otherwise exceedingly unpleasant moment.”

So there is that: for some people airport shopping relieves stress and who can be against that? For others, it solves emergencies, and that too can’t be argued with.

Now you want to know how to beat the system when it comes to overpriced water and for that thank travel blogger Amber Hoffman who files at WithHusbandInTow. Her advice: bring an empty water bottle through TSA. Pack it in a carryon bag. Once you clear TSA, find a water fountain. Around the U.S., especially, public drinking water is safe and often tasty. Fill your bottle. Total cost: zero. As for why she does this, Hoffman explained: “The prices charged by airport retail outlets are outrageous. More than that, though, anytime we can prevent a plastic bottle from being purchased and then discarded should be encouraged.”

If you are embarrassed about being cheap, smugly play the environmental card, and you just won. And you saved $5.

—Written by Robert McGarvey for MainStreet

This article is commentary by an independent contributor. At the time of publication, the author held TK positions in the stocks mentioned.