Question about sustainability that touches on chemistry

I got a link to the following that makes me . . . curious.

I find the basic concept, that worrying about only one thing is not actually indicative of overall sustainability or greenness very important. I rant a lot about the concept of food miles as the only ecological value of food(an extreme example of some locavore arguments, but not beyond the realm of possibility) and carbon as the only measure of product waste a lot. Some of that comes because a particular factor is easy to measure and easy to track. There is merit in tracking things that have numbers associated with them, particularly in the green movement. At least, that's my opinion as a scientist. Numbers and data ground observations in reality.
I am, though, not convinced that packaging doesn't matter, though. I feel like waste can be at least moderately prevented by careful buying. Do we really need to buy 2 weeks worth of groceries every time? Call me suspicious