For example, last year Karen flew from Asheville, N.C. to Singapore. She spent just six hours there, shopping, before turning around and heading home. Not much of a vacation, but she got her miles -- and that was the point.
Now, business travelers, pay attention -- and join a mileage club now. Here's why:
Companies are cutting back on travel, and when travel is sanctioned, more and more road warriors are being told to sit in coach. That's a perfect time to use those accumulated upgrades. They're easier than ever to earn thanks to ongoing double- and triple-mile promotions. At the very least, you may be able to snag a free coach ticket for the family vacation.
Speaking of family, don't forget to sign up the kids. I've taken my 8-year-old daughter on a couple of flights to Europe in the past two years, and now even she's amassed enough miles for a free ticket -- with a double miles promotion this could put you near elite status instantly.
Now, about waiving those bag fees.
Many airlines only require that you attain the lowliest "elite" status, where you rack up a "mere" 25,000 miles a year to get bag fees waived. That's a nice perk as more and more airlines succumb to bag-fee mania (Virgin America joined the crowd last week).
And what about the lowliest of mileage members: those who haven't racked up enough trips to do much of anything? Well, one of my colleagues recently booked a Delta flight and was assigned a middle seat. She went back to the Web site to see if she couldn't get a better one, but no such luck. All seats were "occupied."
She tried again, but this time, plugged in her frequent flier number, and voila: plenty of seats were now available, including an emergency exit row aisle seat.
So there can be advantages, big and small, to frequent flier programs. And yes, it takes some effort, but just do it. No one should leave money on the table. Not in this economy.
This work is the opinion of the columnist and in no way reflects the opinion of ABC News.
Rick Seaney is one of the country's leading experts on airfare, giving interviews and analysis to news organizations, including ABC News, The New York Times, The Wall Street Journal, Reuters, The Associated Press and Bloomberg. His Web site FareCompare.com offers consumers free, new-generation software, combined with expert insider tips to find the best airline ticket deal.