"I think our guests expect us to push the envelope and try things that are different than what the mass-appeal hotels are doing," DeFrino said.

DeFrino's convinced that some guests don't actually mean to ask for new towels but are much like his teenage daughter, who tosses her towels on the floor at home for no good reason. "Once it's on the floor, you're going to get a clean towel," he said. (Hotel guests, not his daughter.)

The pressure on a mid-priced chain

It's trickier for other hotel chains, where sustainability isn't necessarily part of the appeal to the customer.

The mid-priced chains are competing for a more price-sensitive business and leisure traveler. Hampton Inn, which offers a hot breakfast at its nearly 1,900 company-owned and franchise locations across the country, has two environmentally friendly options for disposable plates, bowls and cutlery: 100% biodegradable Enviroware or Taterware, a resin material made from potato starch.

The chain's takeout coffee cup sleeves are made from 100% recycled fiber, and the towel reuse program simply asks customers using a door hanger to "reuse or replace" towels. No big deal either way, the sign suggests.

"We're delivering these messages in a light-hearted way. ... It's not preachy or paternalistic," said Jennifer Silberman, vice president of corporate responsibility for Hilton Worldwide, which owns Hampton.

More happens behind the scenes at Hampton, which benefits from LightStay, Hilton's company-wide sustainability system that tracks the sustainability of 200 operational practices at nearly 3,900 properties around the world. Hilton has saved more than $147 million since 2008 through efficiency projects, including reporting through LightStay, Silberman said.

Satisfying the luxury guest

You'd think environmental sustainability programs would hit a roadblock with luxury guests, who want the best of everything. Not so, said Sue Stephenson, vice president of Ritz-Carlton's Community Footprints, the chain's social and environmental responsibility program.

"It in no way diminishes the luxury experience," Stephenson said. "We still have the best towels, linens and amenities."

Many Ritz-Carlton guests now use the same sheets two nights in a row (introduced in 2011) and hang up their towels to use another day (introduced in 2009).

"We've not had a single negative guest comment but have certainly had positive guest comments," Stephenson said. "Guests want to see we're doing the right thing."

It helps that the onus is really on the business to be responsible in its construction, hotel operations, food service and landscaping, she said. "The majority of what can be done for the environment is what we can do as a business," Stephenson said.

No matter the price point, no hotelier can afford to lose a guest because he or she doesn't like the way a hotel communicates its message.

Even Kimpton's DeFrino said the boutique chain won't roll out an environmental initiative if tests show that customers don't like it. But in Kimpton's case, DeFrino found that guests approve of their efforts.

"Our guest satisfaction has improved since our green initiatives were introduced, and it's given us confidence that efforts have not deteriorated the guest experience," he said.

The tide may be turning

It's possible that younger people used to recycling and saving water will bring those attitudes into their hotel stays as they age. Ritz-Carlton's Stephenson sees children leading their parents into caring about the environment on their hotel stays.

Betting that more and more consumers want to choose environmentally friendly hotels right now, travel website TripAdvisor is launching its GreenLeaders program this year to let travelers know which hotels have sustainable practices.

About 71% of travelers reported that they planned to choose hotels based on sustainability over the next year, compared with 65% in the previous survey, according to an April 2012 Trip Advisor survey.

Yet while 81% of hotels have some green programs, almost a quarter don't communicate that fact to their guests, said TripAdvisor spokeswoman Alison Croyle.

The website is accepting applications from hotels to qualify for a "GreenLeader" or "GreenPartner" label on the TripAdvisor site based on their sustainable practices. The program will rely on traveler feedback, and any discrepancies could trigger an independent audit of the hotel.

That's information that Genevieve Hein, 33, who always hangs up her towels at hotels to reuse them the next day, would enjoy having.

"Trying to limit my impact on the environment makes me feel good," said Hein, assistant director of residence life at Sarah Lawrence College in New York.