It’s no news that people take stuff from hotels. Whether it’s to snag an unusual souvenir, to get their money’s worth, to make up for being “overcharged,” or because hotels tend to loosen inhibitions, guests take enough things to cost the hotel industry big bucks. To be specific, theft costs hotels $100 million a year, according to an estimate a few years ago by the American Hotel & Lodging Association.

Stealing is a slippery term. Taking what’s left of a mini bottle of shampoo after you’ve used half of it isn’t stealing any more than taking a doggie bag home from a restaurant. And if they’ve put their logo on the bottle — or the pen, which many people also consider fair game — they’re getting good marketing. “Every morning in the shower, I am looking at the shampoos I’ve collected from all over,” admired hotel designer Adam Tihany, who at the time advised clients to brand their little amenities so that they would be taken, told Forbes. “It’s like months of free advertising.” (Packing a full mini bottle on your first day so housekeeping will give you another, like emptying the breadbasket into your handbag, is less cool.)

A couple of years ago, hoteliers were more willing, even eager to go on the record about which items had a way of walking off. In 2012, New York’s Waldorf Astoria hotel massively built its Facebook following — and earned a lot of mainstream press — with an “amnesty” campaign to forgive people who returned items their parents or grandparents had “accidentally” packed.

But now the hotel industry has gotten tightlipped. Researching this story was a challenge: Once I got past the usual suspects — towels, pillows, batteries out of remotes, light bulbs out of lamps, bathrobes, Do Not Disturb signs, and cutlery — I had a hard time getting any dirt.

“I’m not surprised that brands didn’t want to talk,” said Bjorn Hanson, clinical professor with the New York University Tisch Center for Hospitality and Tourism and a frequent industry spokesman about trends. “Brands don’t want to be on record saying, ‘Take as much as you want,’ but they also don’t want to come across as closely tracking it.

A step above shampoo greed are the little things that disappear from room service trays, like bud vases and butter holders. Those cost hotels more than pens and shampoos. “Management does track those,” says Hanson, “but doesn’t respond. They just monitor it so they can price some shrinkage into room service.”

People also swipe pillows. “Hotels do care about those,” says Hanson, noting that pillows cost $18 to $80 each. “If a guest takes pillows, about half the time the hotel will send a letter saying, ‘We hope you’re enjoying the pillows — here’s the invoice.’” And every time, the hotel will notice and add it to the guest’s dossier — when he comes back, he’ll likely be steered toward a website where he can buy hotel linens. And you can trust that the hotel will notice. The data from card keys already gave managers a pretty strong sense of who took what — there’s no blaming housekeeping if they didn’t enter your room — but new technology goes even further, implanting trackable microchips in hotel linens.

And then there’s the beyond-gutsy category, in which you almost have to applaud the thieves for being so audacious. Various stories have been bubbling around the Web about what all has gone missing — Bibles and sex toys that are for sale in minibars come up a lot — especially one in the Telegraph in which hoteliers were unusually forthcoming.

Here are 10 that stand out:

--A $300,000 Andy Warhol artwork, taken from the W Hong Kong.
--A 12-foot model of the Concorde, taken from a Best Western hotel, according to a survey of that chain’s housekeepers. How did no one notice that on its way out?
--A suit of armor, reported in the same survey.
--A grand piano. Former Starwood GM Colin Bennett told the Telegraph about the time three people dressed in overalls strolled into a hotel lobby and wheeled the instrument out of the hotel and down the street.
--Serious plumbing. One guest stripped a Berlin hotel room of its Monsoon showerheads, hydromassage shower units, taps, toilet seats, and sink.
--A stuffed boar’s head. A guest tried to abscond from the Hotel du Vin in Birmingham, U.K., with the mounted head. After he was caught, his friends bought it for his wedding gift.
--A minibar fridge. Lots of people empty it, but one guest at a five-star hotel in Dubai left the bottles and took the unit itself, along with the sofa.
--A marble fireplace. A guest at the Four Seasons Beverly Hills was alleged to have lifted one. (Perhaps not literally.)
--A medieval sword, according to a survey by Caterer and Hospitality magazine. Question: How did that guest make it through airport security?
--A hotelier’s pet dog. WTF?

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