New Delhi, Feb. 4 -- Earlier this year, I was in Dubai-a city Indians now treat like the third long weekend of every quarter. I was travelling with a friend who had proudly picked up a "zero forex" travel card just before the trip. "At least I won't get ripped off abroad," he said.

One afternoon, he paid AED 120 for a quick lunch. The SMS came instantly: Rs.2,910. He frowned. The mid-market rate that day would've put it closer to Rs.2,815. Not a disaster, but enough to feel slightly cheated.

"It's supposed to be zero fees," he muttered. It's a line I've now heard from more travellers than I can count.

The irony is that he did everything right. He avoided airport money changers, chose a card with no visible foreign transaction fee, prel...