100. A World Without Waste: The Radical Power of Smart Design
What if the solution to single-use waste wasn’t more effort, but better design?
In today’s episode, I sit down with Mac Sellars from r.World, an award-winning company transforming concerts and sports venues by making the sustainable choice the easiest one. It’s a story of climate optimism, systems change, and the power of rethinking not just what we do, but how we do it.
Together, we get into some often-overlooked but important truths about single-use waste, how the system needs radical rethinking — not just incremental improvements — and the spiritual practices that are woven into all of it.
If you’re someone who wants to implement more sustainable practices in your workplace or community, or even your home, get ready to be challenged and inspired in all the best ways.
“The single-use experience has been so normalized, but there’s a better way—and people are ready for it.”
Key Takeaways:
Reusable > Recyclable
Recycling, especially plastic, is largely ineffective. Mac emphasized that true sustainability comes from reusable systems, not just swapping one disposable product for another.Design for Ease, Not Effort
Sustainability should feel seamless and r.World creates systems that mirror the single-use experience, making it easy for people to participate without even realizing it.Cultural Influence Is Powerful
Artists and athletes can be key drivers of behavior change. When figures like U2 or venues like Red Rocks demand sustainability, fans and operations tend to follow suit.Choice Architecture Matters
Removing the burden of decision-making helps people adopt sustainable habits. Making the sustainable choice the only choice reduces confusion and increases compliance.Narrative Shifts Drive Behavior
We must challenge traditional narratives of individual guilt and personal responsibility, encouraging listeners to shift toward collective opportunity and system-wide change.Spirituality and Stewardship
While not the main focus, Mac introduced the idea that true materialism — caring deeply about what we use and how — is a spiritual act of stewardship.
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“Sometimes the most powerful thing we can do is take the choice out of the equation and just build a better system.”
About Our Guest
Mac Sellars is the Strategy & Innovation Lead for r.World, an award-winning company eliminating single-use waste through reusable foodware services. Mac drives process, product, and partnership development across the company, helping r.World to more effectively deliver on its mission to create a world without waste.
As part of his work, Mac sits on the advisory board for Minnesota's EPR policy, as well as PR3's global reuse industry standards panel, collaborating with diverse stakeholders to enable a flourishing reuse industry.
Prior to r.World, Mac received his Master’s of Divinity from Harvard Divinity School, where he received professional and theological training from faculty across the Divinity, Law, and Business schools.
About r.World:
r.World is North America’s leading reuse platform, on a mission to eliminate single-use waste through scalable, reusable foodware systems. Founded by sustainability pioneer Michael Martin, the company traces its roots back to the 1990 Earth Day stadium concerts, which Martin produced to help relaunch Earth Day as a global event.
Dubbed the “Guru of Live Event Greening” by Billboard, Martin spent decades introducing environmental innovation to the music industry, partnering with artists like U2, Paul McCartney, and Dave Matthews Band. In 2017, he launched the reuse movement in the U.S. with U2’s Joshua Tree Tour, debuting what would become r.World’s flagship product: the reusable r.Cup.
Today, r.World collaborates with venues, artists, sports leagues, NGOs, and national policymakers to build the infrastructure and momentum for a true reuse economy—one designed to end our addiction to single-use and create a more sustainable future for all.
