I've been research director on some communications projects focused on sustainability -- trying to get the public to understand the concept. It's easy to get fooled into believing that people understand what you're talking about, only to discover later that their perceptions were quite different from what you thought. There are certain parts of the sustainability story that are easy to tell -- resource depletion or economic viability, for example -- and then there are parts of the story that are nearly impossible to tell. One of these is the relationship between diversity and resilience (especially when it comes to sub-optimal, even maladaptive, traits and forms). Across the long term a diversity of imperfections makes whatever system more resilient and ready for changes.
Evolutionary biologists have the best grasp on it, since non-optimal forms are the stuff that evolutionary change is built of. People who take the long view, ecologists like Wendell Berry or meta-farmers like Sharon Astyk, understand that this applies to our food system as well. At the moment our tendency toward monoculture, genetically narrow breeds, and our one-size-fits-all approaches make us vulnerable to any kind of change (whether it’s a new pest, climate weirding or the declining availability of cheap fossil fuel). Things always change eventually, and when change comes we'll want more rather than fewer varieties to choose from.
But Americans tend to believe there is always a "best" variety, and it is very, very hard for most people to really see the value in having a system full of waste and noise and inefficiencies (that is, diversity).