It's not clear the reusables have done that in any significant way. Indirect measures suggest that plastic bag production has remained relatively steady.
What is clear is that reusables have taken off as a cultural phenomenon, social statement, and even art form.
And, some worry, not all to the good.
"People are accumulating too many of these, so we're back to the original problem," said Vince Cobb, a Chicago businessman who reinvented himself as a reusable-bag expert and salesman at www.reuseit.com.
"The whole thing is to consume less," he said.
So he was appalled when the Chicago Bears gave away 40,000 reusable bags at a 2009 game. Many were thrown away by halftime.
Perhaps it was inevitable that a culture hooked on shopping would find itself obsessed with bags.
More companies are giving bags away as promotional items - eco versions of the coffee mug. Last week, Target gave away a million.
For many companies, "getting their name out in what is perceived as a socially and environmentally responsible way is a good thing to do," said Leonard Lodish, professor of marketing and vice dean of social impact at the Wharton School of the University of Pennsylvania.
They come in every form imaginable: Stretchable, foldable, stuffable, made from recycled plastic bottles and juice cartons. A Philadelphia woman even crochets throwaway plastic bags into new reusables.
Not every reusable bag is environmentally equal. A nonwoven polypropylene bag, for example, would have to be used just 11 times to make up for the negative effects of a plastic bag used one time, according to a British Environment Agency study that compared bags. A cotton bag, however, would have to be used 131 times.
