Before the sun could rise over Los Angeles International Airport on a recent Tuesday, hundreds of Uber and Lyft drivers had formed a queue nearby, stretching around the block. It was 5 a.m., and the waiting game was about to begin.

In a few minutes, the line of cars would file into a fenced-off parking lot, a mile from the arrival terminals. It is known officially as the Transportation Network Company Staging Area, but drivers call it the “pen,” where they wait to be matched with passengers getting off flights.

The spot used to be a prime place to catch rides and earn decent money. But these days, there seem to be few rides to go around. Veronica Hernandez, 50, parked her white Chevy Malibu at 5:26 a.m. and opened the Lyft app to check her place in the queue: 156th. It would be an hour and a half before her first ride of the day.

“You have good days and bad days,” Ms. Hernandez said, swiping through a screen showing her daily earnings on the app that week: $205, $245, $179. “Hopefully it’s a good day.”

Like ride-hailing drivers across the country, Ms. Hernandez has seen her pay decline in recent years, even as the demand for her work feels greater than ever. And with the cost of gas and car insurance rising, the already slim margins of gig work are becoming less workable by the day, she said. No place is more emblematic of these problems than LAX, one of the busiest airports in the world but one of the most difficult places for gig workers to earn a living.

“It used to be a real way to earn money,” Ms. Hernandez said. “Now you can barely survive on it.”