From reading their materials, it seems that Macpac has an environmental principle based on the old ‘3 R’s’: reduce, reuse, recycle. They state that they attempt to make good technical gear that is designed and built to last a long time: in effect, making gear of substance that will last, rather than short lived outdoor fashion items that will need to be replaced in a few years. I have always been impressed at how durable their equipment is, and so had been hopeful that this company would be a leading light in terms of sustainability.
However, with the information that’s publically available it is hard to even rate them at this point.
A longer profile is available here.