Dasha loved American schools, and Zahar still speaks in a jumble of English and Russian, but Navalny had bought round-trip tickets.

NEWYORKER: Net Impact

Qualifying service men and women may also be given free round trip airline tickets to enable their family or close friends to visit them while they are being treated at the medical center.

FORBES: 12 Days of Charitable Giving 2012: Fisher House Foundation

In 1997, the small businessman flew from Jogjakarta 220 km to Jakarta only to discover he needed to buy three additional round-trip tickets so inspectors could check out his food company, Rakit Barokah Food.

CNN: Big Little Problems

Air Canada now breaks down round-trip flights as separate one-way tickets on its Web site, showing you exactly what you pay for each leg.

CNN: Pros and cons of a la carte airfare pricing

One hint, however, of just how much spoilage is out there: Southwest issues free tickets to customers after 16 credits are earned (eight round-trip flights), and the certificates expire after a year.

WSJ: Saving Frequent-Flier Miles From the Ax

Fulham manager Roy Hodgson was understandably keen for his team to avoid a road trip and claimed the 1, 140-mile round trip would be a "disaster" for the 2, 500 Fulham fans who have bought tickets for the game.

BBC: Europa League semi-finals given provisional go-ahead