Heard the one about the four Australians having dinner in a New York City restaurant? The food was superb and the service was cheery and flawless.
After paying the bill, the Aussies left what they thought was a generous tip - just over 10 per cent.
And that's what sparked the problem.
The waiter went into a huddle with the restaurateur.
The owner came over and was extremely apologetic.
"Sorry about the meal," he said.
"We don't get it right every time."
No, the Aussies protested - the food was fantastic.
"And the service?"
"Couldn't have been better. You have a wonderful waiter."
The owner's face reddened as he looked at the tip.
"C'mon, guys - if everything was so great you'll have to do better than this lousy tip."
The puzzled Australians tossed more cash into the tip tray.
The story may be apocryphal - but the message is all too real.
Australians are certainly not seen as the world's most generous tippers - though anecdotal evidence suggests this is mainly because we don't know how much to tip and often rely on outdated advice.
For instance, guidebooks routinely describe New Zealand as a non-tipping nation. But this has changed as more people in the country's hospitality industry travel to other countries.
While Kiwis don't expect tips, gratuities have become commonplace in some upscale restaurants - but are almost totally absent in others.
It can be very confusing.
But, when in doubt, there's no harm in tipping 10 per cent after a good experience in a quality restaurant - or a dollar or two to the hotel bellhop who delivers your bag.
The same is increasingly true in other South Pacific island countries.
Opponents of tipping say it's like tossing sweets to roadside kids - and raises expectations. Others counter that it's too late to fight tipping which has become the norm almost everywhere.
True non-tipping nations are all but extinct. Stories were often told - when Mao Zedong called the shots in mostly-off-limits China - about staff going to great lengths to return tips, particularly monetary gifts for cleaners that were left in hotel rooms. Not any more. In China, tipping has become commonplace.
Some guidebooks describe Japan and South Korea as non-tipping nations - and, while tips aren't generally expected, they are seldom knocked back.
North Korea is possibly the world's only surviving non-tipping society. Knowing this, I gave a Pyongyang waitress a large tip to see what would happen. She made a point of returning the tip to me - making sure the eyes of my minders, Mr Kang and Mr Ri, were on her as she did so.
Tipping etiquette can be a minefield:
- Waiters in New York City have reportedly argued with customers over poor tips, even chasing them down streets.
- A London cabbie followed me into a lift and asked, menacingly, "Oi, where's mine?" when I forgot to tip.
- A friend's exit from a Prague restaurant was blocked after she didn't leave an expected tip.
- A Johannesburg waiter, taking my credit card, asked: "Shall I add the tip to the total or will you be tipping separately in cash?"
- Waiters at a popular Manila restaurant carry rubber stamps in their jacket pockets, stamping bills with the words: "Tip Not Included."
Some waiters don't want tips added to credit cards, saying owners retain these amounts.
Where a "service charge" is added it's acceptable not to tip - but waiters often complain that they see nothing of this levy.
Australians who oppose tipping argue that staff here earn reasonable wages - so shouldn't become reliant on additional tips.
Nevertheless, modest tipping is common.
At the other extreme is the situation in some US casinos where tips are so good that staff routinely kickback all or some of their wages to supervisors - just for the privilege of working there.
One scam that angers Australian waiters involves large office groups going out together, generally for lunch. When the meal ends, each guest puts a share of the bill - including tips - on the table.
A villain among them pockets this mound of cash, suggesting it'll be easier (no-one thinks to ask why) to put it all on his or her credit card.
So, the bill is by credit card at the till - with no tip. The perpetrator has wangled a free meal by keeping tips intended for the staff.
According to David Goldman, general manager and director of Sydney's Goldman Travel, "it's always nice to leave a tip".
"It's expected more and more - and it's polite to reward a great waiter who's stood on his or her feet for hours and who makes sure you're comfortable." Poor service? Goldman advises not tipping and telling the waiter why.
"Tipping is an issue for the typical Aussie travelling abroad," says Michelle Toner, owner of Brisbane's Travelscene in Greenslopes Mall.
"It certainly doesn't help when nearly every country has different tipping customs.
"Ask a local what's standard," she suggests.
"In countries where wages are poor, tips boost income."
While 10 per cent is a rough guide in Australian restaurants (and, staff say, many tip less or even nothing), in the US it's positively mean.
Ten per cent used to be normal in the United States - excluding New York.
But as 20 per cent increasingly replaces 15 per cent in New York, so 15 per cent has crept in to replace 10 per cent elsewhere in North America.
A dollar per bag (minimum $2) remains a good rule of thumb for hotel bellhops (less where wages are low; more where wages are high). And the equivalent of $1 or $2 is fine for hotel staff opening taxi doors.
In taxis almost everywhere it's common to round up to the nearest dollar.
Guides in game parks or on city tours commonly get $10 to $20 per person per day for private services (the lower sum in low-wage countries). But if you're a passenger on a tour bus, it all depends on quality. Some passengers don't tip, others give $5.
Some travel experts advise $5 or $10 to hotel concierges soon after check-in to guarantee you'll be recognised and helped each time you enter the lobby. (Others suggest this is unnecessary). One disputed definition of "tips" is that it stands for "to insure prompt service".
Travelscene's Toner says confusion over what to tip arises most commonly in restaurants - though 10 to 15 per cent of the bill is most common.
It's good advice to ask a hotel concierge (or local contact if you have one) what's common in a city.
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