By Christina Warden

This Labor Day, Starbucks employees don’t just want a pat on the back for being hard workers. They want their company to serve up stable schedules along with all those fancy coffee drinks.

Recently, Starbucks vowed to make life better for its 130,000 workers by improving its scheduling guidelines. This was in response to a heartbreaking profile in the New York Times of Jannette Navarro, a barista whose erratic schedule has wreaked havoc on her and her son’s lives.

But Starbucks’ commitments, such as giving one week’s notice of employee schedules and discouraging managers from scheduling workers for back-to-back opening and closing shifts, fall short.

One week’s notice is a low standard; even Walmart says it gives three weeks notice of schedules.

Sadly, the unfair scheduling practices that cause chaos in the lives of Starbucks employees are far from unique. Erratic scheduling has increasingly become the norm in hourly wage service industries, especially with the introduction of predictive scheduling software.

Of the 20 million workers in low-paying jobs, 59 percent of full-timers have to deal with volatile schedules, according to a report by the Center for Law and Social Policy, the Retail Action Project and Women Employed.

It’s even worse for part-timers. Many learn their schedules only two or three days in advance.

And they might be scheduled as “12 BD,” which means they’re expected to show up at noon and leave when “business declines,” which could be any time at all.

The personal consequences of chaotic scheduling are severe. A waitress or home-care worker might give up on college because she can’t plan for classes or budget for tuition. A mother might pay for child care, spend an hour or more commuting and show up at work, only to be sent home without pay because it’s a slow day.

Companies that rely on these practices claim that they do it to optimize profits, but that’s dubious, since such scheduling can lead to unfriendly service, poor performance, burnout and turnover.

By contrast, higher worker satisfaction reduces costly turnover and is correlated with higher customer satisfaction. It’s no wonder that Starbucks customers, employees and shareholders are calling on the company to do more.

So are some members of Congress. Recently, Reps. George Miller, D-Calif., and Rosa DeLauro, D-Conn., and Sens. Tom Harkin, D-Iowa, and Elizabeth Warren, D-Mass., introduced the Schedules That Work Act.

It would require that workers get their schedules at least two weeks in advance, and it would protect all employees from retaliation for requesting a more flexible, predictable or stable schedule. It would also pay workers for the four hours of work they were scheduled for if they showed up on time but were then sent home early because business was slow.

This bill could make a big difference, but it may not pass.

So it’s up to companies like Starbucks to take the lead, do right by its workers and set an example for other companies.What do you want to get at Starbucks? Scheduling practices that are humane, as well as good for business.

That would be a nice way to celebrate Labor Day.