Q: "I'm trying to get a refund from United Vacations, but nothing seems to be working. I booked a car-and-air package from Denver to Lihue, Hawaii, through United Vacations recently. I registered my airfare through Yapta.com, which alerts you when the price of your flight drops.

"A few weeks later, I received a notification that the price of my flight had fallen by $733. That amount of money is significant to me. I called United Vacations, but was told I couldn't get a refund. Had I booked through United Airlines, I would have received a voucher.

"Is there anything I can do to persuade United Vacations to change its mind? I will happily rebook another trip with United Vacations if this is rectified properly."

Mary McInnis-Efaw, Fort Collins, Colo.

A: You would think United Vacations — which is owned by United Airlines — would offer the same no-questions-asked refund when fares drop.

Not necessarily. When you book a flight on United, you are entitled to a refund of the difference between the new, lower fare and the old fare, minus a $100 change fee. But if you buy a package through United Vacations, you're subject to a more complex set of terms and conditions that don't seem to offer any such guarantee.

Part of the reason is that United Vacations is selling tickets for other airlines, including Air Canada, US Airways, Hawaiian Air and various regional airlines. All of the air carriers have different refund rules. Another part of the reason is that tour operators and travel agencies that offer package deals sell what are known as "consolidator" fares, or bulk fares that have more restrictions than the average ticket.

Still, I think it's reasonable to assume when you're dealing with a company owned by United Airlines, and you're also flying on United, that you could qualify for the refund. And $733, as you point out, isn't chump change.

At the time you made your reservation, United wasn't the only airline that offered refunds when fares fell. But I don't think airlines should.

I don't run back to the department store three months after I buy a pair of shoes and demand the difference between the price I paid and the sale price. I think the only reason airlines feel they have to offer these refunds is because they play price games, offering a rock-bottom ticket price one minute and quadrupling the price the next.

Maybe if they stopped that nonsense, you wouldn't feel ripped off when the price of your airline ticket fell.

Calling United Vacations was a good first step, but a quick, polite e-mail to the company, explaining why you felt a refund was in order, might have worked better. Often, call center agents are nothing more than script-reading drones who are incapable or unable to appreciate the nuances of your compelling arguments. A concise e-mail is more difficult to dismiss and can easily be forwarded to a supervisor if you're turned down.

I contacted United Vacations on your behalf. It sent you a voucher for $733.

Christopher Elliott is the ombudsman for National Geographic Traveler magazine. You can read more travel tips on his blog, elliott.org, or e-mail him at celliott@ngs.org.