My city cut down on plastic bag usage considerably by introducing a $0.07 excise tax on every disposable grocery bag, but I don't think that would have been politically tenable if there weren't already a lot of people using reusable bags.

Plastic packaged goods, I don't know. . . I almost wish that some organization would launch a big campaign against Trader Joe's to get them to reduce their packaging use. It's going to be really hard to convince a bodega to stop selling packaged goods, for all sorts of reasons. But Trader Joes has enough control over their supply chain to do it. Their clientele is bobo enough to maybe be a bit easier to get on a bandwagon. They individually shrink wrap the broccoli, so they're a pretty easy target. And they're popular enough that a successful campaign could have a big cultural impact.