Use reusable bags when shopping instead of plastic bags.
For about $1 you can purchase recycled reusable bags at most stores. Even though you are paying for them, they are still very ecOnomical. They hold about three times as much as a plastic bag...cutting back on the trips you have to make to and from the car. They will help reduce the amount of trash added to landfills. They can also be used for toting items other than your groceries...toys grandmas...crafting items from room to room... The possibilities are endless.
There are some really cute bags sold at Toys-R-Us for $1.25.