This article from How Stuff Works says 25 million American travelers overseas were victims of these scams in 2008. Here are the scenarios:
1. Good Samaritans - scam artist is trying to help you out
2. Unscrupulous cabbies - literally cab driver takes you for a "ride"
3. Money changing "errors" - visitor unfamiliar with local currency
4. Create a distraction, steal your wallet - beware the woman who undresses
5. Fake police officers searching for counterfeit bills
It's easy to be victimized traveling abroad because every traveler is vulnerable in a new and different environment. Add jetlag to that and ecco!, an easy target. I was once a victim of a money changer in Bali who swore he didn't have larger bills to give me hence he had to count thousands of rupiah as I stood soaking in the hot and humid air while he slid his hand over the bills and pulled out $12 worth of rupiah. Thank goodness the hotel staff where I stayed in Nusa Dua helped me recover the money from the changer. And yes, he didn't have to count endlessly because as it turned out, he had larger bills to spare.
About taxis, I have yet to figure out the night and weekend surcharges, the per bag fee and the charge for calling a taxi to pick me up from the hotel or specific location vs. hailing them on the street. This is especially true in Europe. I study my guide books carefully before going on a trip so I know what to expect. But sometimes, I'm still in the dark. Public transportation is cheaper and more colorful but buying a ticket from a machine may take a few minutes to decipher. It's high tech and the language of instruction is often Greek to me.
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