Peter asks a great question: Single use versus recyclable...
I think the strongest reason to use compostable, single use containers is that a shocking number of plastic containers never make it to the recycling center.
That is the user-centric, behaviorist argument.
The question of which is "better" in terms of total energy cost and impact on the planet is a much bigger question.
There are so many plastics out there...some can't be recycled at all, some are too expensive to recycle...however, few materials are infinitely recyclable...In Cradle to Cradle, the authors talk about "downcycling"... glass is technically totally renewable, but once you mix colored and clear glass you have an interior product: it can no longer be used for it's original purpose. Old tires can be ground up and used in roads or as sandals, but then reach a dead end.
The plus of corn (or beet or potato or rice) plastics is that they can be grown sustainably and possibly without petroleum input. That's a real advantage over petroleum-based plastics.
