Airline pilots won pay raises worth billions of dollars in new labor deals last year. Flight attendants are now pushing for similar improvements.

Flight attendants from United Airlines, American Airlines, Southwest Airlines, Alaska Airlines and others picketed Tuesday at dozens of airports around the U.S., demanding higher wages and better quality of life.

“We have been in a period of austerity for 20 years, and it’s time the industry paid up,” said Sara Nelson, president of the Association of Flight Attendants-CWA, which represents cabin crews at United, Spirit, Frontier and others.

The demonstrations mark the first mass pickets jointly held by the labor unions, which represent more than 100,000 flight attendants at U.S. airlines between them. New labor deals would come not just on the heels of pilot contracts, but also pay increases won by auto workers, Hollywood writers and at major companies like UPS.

Flight attendants at most of the largest airlines haven’t received pay increases since before the pandemic, which paused contract talks, while the cost of living rose sharply in recent years.

American and other carriers told CNBC they are optimistic that they will reach agreements with their flight attendants in the coming months.

Labor costs and fuel account for airlines’ two largest expenses.

Delta Air Lines, whose flight attendants aren’t unionized, started paying flight attendants for boarding at half their hourly rate in 2022. (The Association of Flight Attendants started a new union drive there before the pandemic.)