Wait till you hear about the plastic bag crazy. Pretty much all the chains got rid of them in my area and began selling the reusable bags. At about 2.50 each. One store I liked used to have old cardboard boxes but they want you to buy the reusable bags as they make about 2 dollars in profit per bag and the average costumer buys 1 bag per 100 in groceries. That alone is a2% increase on average in profits for the grocery chain. That is huge for them.
Worse is that they take about 50 times the energy to produce and they figure the average bag is only used 5 times before they end in a land fill. The net result is a 2.5% increase in your grocery bill and almost 10 times the increase in GHG compared to a plastic bag.