This story has been updated from 9:43 a.m. ET on Wednesday, June 14, with a comment from American CEO Doug Parker and with a clarification that United has been adding seats on its aircraft for several years; the effort is not new. 

Both American Airlines Group (AAL) and United Continental Holdings (UAL) said, in different ways, that airline seating is getting tighter.

Speaking at an investor presentation on Tuesday, June 13, United's Chief Financial Officer Andrew Levy said United has been adding seats on nearly all of its 743 mainline aircraft.

Meanwhile, American said the airline's new Boeing 737 MAX will have a minimum seat pitch -- the distance between seats -- of 30 inches rather than 29 inches as previously stated.

"Adding more seats to the airplane is a very profitable way to grow," Levy told investors. "It's not a very significant investment, but it can drive better margin performance."

Levy restated the belief, common in the aircraft industry, that despite continuing chatter about cramped aircraft, passengers generally make it clear in their ticket buying that comfort isn't the primary consideration.

"For many of our customers, despite what they say, they care mostly about pricing and schedules," Levy said.

According to a chart Levy displayed, United has increased the number of seats on its Airbus A319s to 128 from 120. On the Airbus A320, seat count goes to 150 from 138.

Boeing Co.  (BA) 737-700s will have 126 seats, up from 118. Boeing 737-800s will have 166 seats, up from 154. Boeing 737-900s will have 179 seats, up from 167. Boeing 757-300s will have 231 seats, up from 213.

Among United's widebodies, Boeing 767-300s will have 214 seats, up from 183. Boeing 777-200s will have 364 seats, up from 303. The Boeing 787s, which are new, won't get more seats, and the Boeing 747s, which are being removed from the fleet, also won't get new seats.

United spokeswoman Megan McCarthy said Wednesday that Airbus reconfigurations were completed in 2014; Boeing 737 and 757 reconfigurations will be completed by next summer; 767-300 reconfigurations will be completed in 2018 and Boeing 777-200 reconfiguration will be completed this summer.

Levy did not discuss pitch, or the distance between seats. Speaking at a Senate hearing last month, Sally Greenberg, executive director of the National Consumer League, said average pitch has declined to 31 inches from 35 inches before deregulation.

"Americans are getting bigger, we're getting heavier, and we're being crammed into smaller and smaller spaces," Greenberg said. Nevertheless, the fastest growing U.S. airlines are Spirit and Frontier, which generally offer just 28 inches of pitch.

At American Airlines annual meeting on Wednesday, CEO Doug Parker said the 30-inch pitch in the new Boeing 737 MAX aircraft "feels like a 30 inch pitch because the seats are thinner."

Parker said the airline will absorb a cost, which he did not disclose, because it will put in fewer "main cabin extra" seats, which come with more legroom and a higher ticket cost.

In its announcement Tuesday, American said, "Last month we shared plans that our Boeing 737 MAX would arrive with three rows at 29-inch pitch. 

"Since then, we have received a lot of feedback from both customers and team members, and after taking a fresh look at the interior of that plane," the carrier said. "American has decided to space all Main Cabin rows with at least 30 inches of pitch.

"It is clear that today, airline customers feel increasingly frustrated by their experiences and less valued when they fly," it said. "We can be leaders in helping to turn around that perception, and that includes reviewing decisions that have significant impact on the flying experience."

The MAX will still be configured with 172 seats. American said it found space to eliminate the 29-inch rows by switching one "main cabin extra" row to "main cabin."

United fell 0.48% to $77.11 on Wednesday and American declined 0.08% to $49.41.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.

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