When hotels replace single-use toiletries with refillable dispensers, or companies strip unnecessary items from product bundles to cut waste, they may expect consumers to hail these changes as environmentally responsible.

However, a new study has identified what the authors call ‘sustainable additive bias’ - a tendency for consumers to view businesses as more sustainable when they add eco-friendly items rather than remove them, even when removal leads to lower waste and a smaller environmental footprint.

Sustainability is not about adding more eco-friendly products

“People often assume that the more eco-friendly products a company provides, the more sustainable it must be. But sustainability is not necessarily about adding more. It is often about reducing what we produce, conserving resources and avoiding things that people do not really need. An extra product does not become sustainable simply because it carries an eco-friendly label,” said Dr Diletta Acuti of the University of Bath School of Management.

“Reusable cups, water bottles and tote bags can all be good alternatives to disposable products, but people increasingly have cupboards full of them. I have accumulated around 20 tote bags myself, many given away at conferences and events. One reusable bag is useful; producing and distributing far more than people need risks turning a sustainable idea into another form of overconsumption.”

Published in the Journal of the Academy of Marketing Science, the research by the University of Bath, Audencia Business School, emlyon business school, University of Portsmouth, ISM University of Management and Economics, and University of the Aosta Valley drew on nine studies covering hotels, consumer products, conferences, festivals and trade shows, and a field study involving hotel guests.

The researchers found that people consistently rewarded visible eco-friendly additions such as reusable bottles, organic toiletries and sustainable gift items. But they gave little credit to businesses that reduced or removed products. In one hotel experiment involving 302 guests, rooms stocked with a larger selection of eco-friendly amenities were rated as more sustainable than rooms with a minimal set.

“The problem is that adding something is visible, while removing something is not. Consumers can see the bamboo accessory, reusable bottle or eco-friendly hotel toiletry, and may interpret it as evidence that a company is making an effort. When a business removes unnecessary products to save resources, customers cannot see what is no longer there, so that action may receive much less recognition,” Dr Acuti said.

The researchers said they were encouraged that the study showed the ‘sustainability additive bias’ can be reduced by clearly communicating the environmental effort behind removing products, and by retaining highly recognisable sustainability signals, such as refillable bottles or reusable products.

“Our findings highlight the urgent need for businesses, policymakers and consumers alike to rethink the assumption that sustainability always means adding more environmentally friendly products. Business should explain when items have been removed to save resources or prevent waste. They could also make reduction more visible, for example by replacing several miniature toiletry bottles with one clearly labelled refillable dispenser for example,” said Dr Acuti.

“A hotel may look greener when a room is filled with eco-labelled toiletries and other sustainable-looking products, but providing more items can also mean more production, packaging and waste. Hotels should explain when amenities have been removed for environmental reasons, so guests understand that having fewer products is a deliberate sustainability measure rather than a reduction in service.”

The authors say policymakers and environmental organisations should place greater emphasis on waste prevention, reduction and “less but better” approaches. Without clearer communication, organisations may receive more recognition for handing out another green product than for avoiding the need to produce it.

“Our central message is that we need to learn that less can be better. We are accustomed to seeing addition as improvement, but removing an unnecessary product does not mean reducing quality. Sometimes it creates a more efficient service and a genuinely better environmental outcome,” she said.

“Companies can produce individual products more sustainably, and that is important. But if we continue consuming more products overall, we still use more resources. Sustainable production alone cannot solve the problem of overconsumption. We need to question whether another product is useful or necessary in the first place,” Dr Acuti said.