The Bambu plate, while not breaking down as fast as the Whole Foods container, is on its way to turning into soil. While there are some environmental issues associated with bamboo crops, such as artificially accelerated growing techniques and the supplanting of old growth forests, Bambu says their plates are made from 100% organic bamboo, which generally comes from well-managed bamboo stands. Since it’s thicker and more rigid than the Whole Foods container, and made from bamboo peeled directly from the stalk, it makes sense that it would take longer to degrade.
However the issue raised about still stands: why do compostables matter if most of them won’t be composted? There are two main reasons. The first is litter; when plastics make their way into the environment, they don’t ever really break down into natural constituents; they just become smaller and smaller pieces of plastic. These bits often make their way into waterways where animals ingest (or try to ingest) them, blocking their digestive track and killing them quickly. They may also absorb the chemicals the plastic is made from, killing them slowly. When we eat fish that has been snacking on plastic pieces, we end up with those toxins in our bodies too.
Then there’s leaching. When compostable packages eventually (eventually!) break down in a landfill, they are reduced to natural constituents like cellulose or bamboo fiber. When plastic is stuck in a landfill, it will, over time, leach the toxic chemicals used to make the container, which can eventually work its way into local water tables. Yep, that means that we (or the animals we eat) end up drinking that water.