Less work for staff in hotel housekeeping?

First came the pleas to reuse bathroom towels at hotels as a way to help the environment.

Now, more operators are asking guests to skip housekeeping altogether — and they’re willing to sweeten the deal. Under programs with names like “Make a Green Choice,” “Greener Stay” and “Green for Green,” hotels are rewarding customers who choose not to have their rooms serviced during their stay with loyalty points, food and drink vouchers or other incentives.

Such opt-out programs have been around the industry for more than 10 years; Starwood, now part of Marriott, started Make a Green Choice in 2009. But observers say the practice has been spreading more in recent years, especially at mid-level properties.

“We might be at the beginning of a cultural shift away from housekeeping as a daily practice,” says Paul Bagdan, a professor of hospitality at Johnson & Wales University. “People are starting to say, ‘Yes, I don’t need it.‘”

Mr. Bagdan says that for hotels, encouraging guests to cut back on housekeeping has several benefits: It lets operators take environmentally-friendly steps by using less water, electricity and cleaning product; it helps them save costs on labor; and it encourages guests to enroll in rewards programs, which has value for the chains.

At industry giant Marriott International, 23 of the company’s 30 brands take part in the “Make a Green Choice” program, though it’s up to individual owners and operators to participate. Depending on the brand, guests usually get between 250 or 500 points a day for declining housekeeping. Spokesman Jeff Flaherty said in an email that more than 2,800 hotels offer the option in the U.S. and Canada.

But as these programs have grown in popularity, they’ve also prompted pushback — especially in Marriott’s case.

The labor union Unite Here released a report that said housekeepers reported losing hours because of the program. When rooms were eventually ready to be cleaned, according to the report, they were dirtier than those that were serviced daily and took more time and products to clean. The vast majority of workers said they still provided some services to guests who opted out of housekeeping.