A reader recently paid $600 for the privilege of staying home.

That was the accumulated cost of canceling tickets on a Delta flight for her family of three. The airline, along with other major carriers, raised its change fees to $200 per ticket last spring. The three tickets that cost her $500 apiece turned into credits worth $300.

The financial loss was expected, but the date by which she would have to rebook or lose the credits was a surprise. The traveler doesn't have a year from the time of the originally scheduled flight to use the credits. She has a year from the time she booked the flight to spend those $300 Delta credits.

Early planning created double trouble. It was too early to see that her situation might change. And now, she has only eight months, not 12, to concoct another trip by air.

Buying refundable tickets generally isn't a reasonable way to insure yourself against this. In early January, for instance, Delta's nonrefundable nonstop seats to Orlando from MSP cost around $350; refundable fares start at $1,000. That difference makes $200 seem like a drop in the bucket.

As for airlines, their buckets overflow. In 2012, Delta took in $778 million in cancellation and change fees (the figure was $2.6 billion for the industry as a whole). Delta is on track to increase that haul, having made $411 million in the first two quarters of this year.

OK, so the argument goes, these fees help keep the airlines flying, and offering reasonable fares. But there's more good news for the reader. The money she'd paid to upgrade to economy-plus seats was fully refunded. Don't tell Delta, but she was pretty sure the airlines would have found some way to claim a portion of that money, too.

Send your questions or tips to travel editor Kerri Westenberg at travel@startribune.com, and follow her on twitter @kerriwestenberg.