Airlines are increasingly charging passengers extra for a window or aisle seat, leaving families who want to travel together paying extra to sit together.
The Associated Press reported that the move — a bid to boost revenue — was also designed to reward frequent travelers, who themselves may not have to pay extra for the seats.
"The customers that are more loyal, who fly more often, we want to make sure they have the best travel experience," the AP quoted Eduardo Marcos, American Airlines' manager of merchandising strategy, as saying.
Passengers must increasingly reserve the select seats in advance at a cost of $25 or more each way, the AP wrote.
The Oregonian cited a Jan. 3 tweet from American Airlines that served as an announcement of sorts for the new policy: "To ensure seats together, Preferred Seats is a great option. Customers can purchase starting at $4."
The tweet linked to a section on American's website about how to secure seats together for extra money.
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The Oregonian cited airline industry consultant Robert Mann as saying carriers were increasingly reserving aisle, window and other choice seats for those willing to pay extra, while others block off a section of the plane for elite frequent fliers.
The result was especially noticeable when trying to book seats together on packed flights during the holiday season.
"All of a sudden the cabin gets pockmarked," Mann said. "That's where parties of two or more get tripped up."
Since last summer, American, Delta Air Lines, Frontier Airlines and United Airlines had increased the percentage of coach seats requiring some kind of extra fee, according to the AP. Allegiant Air and Spirit Airlines charge extra for any advanced seat assignment.
It's among a number of policies implemented by US airlines recently that have been criticized as family unfriendly.
Last month, United Airlines ended its policy of allowing families traveling with small children to board early, USA Today reported.
The AP quoted Khampha Bouaphanh, a photographer from Fort Worth, Texas, as saying the cost of his family trip to Disney World would have ballooned had he chosen to sit with his wife and 4-year-old daughter.
Bouaphanh so far hasn't paid the extra $114 roundtrip in fees to reserve three adjacent seats.
"I'm hoping that when we can get to the counter, they can accommodate us for free," he said.
"Who wants to fly like this? It gets more ridiculous every year."
Airlines say their gate agents try to help family members without adjacent seats sit together, especially people flying with small children, however there are no guarantees.
Senator Charles Schumer reacted to the AP report by urging airlines to allow families with young children to sit together without paying extra.
A separate AP story cited the Democratic senator from New York as asked Transportation Secretary Ray LaHood to issue rules preventing airlines from charging parents more to sit next to kids.
"A parent should not have to pay a premium to supervise and protect their child on an airplane," Schumer wrote in a letter expected to be sent Sunday to Nicholas E. Calio, the trade group's president.
In 2010, Schumer convinced five big American airlines to promise not to charge fees.