Ban all disposable bags
It won't take long for people to learn to how easy it is to bring their own bags. Somehow, I've gone two years without taking any paper or plastic bag for my groceries or purchased items.
San Fransisco did it, and everyone said the world was going to end, but they have never received one complaint.
Hannah Rose commented
There should be a service that allows you to bring your reusable bags back (perhaps a rental service). This way, if you forget your bag, you can just borrow another, and bring them all back on your next visit.
Also, produce bags need to be relooked at. Even stores like whole foods, that encourage using reusable bags, have small plastic bags available to put your vegetables in.
NOTE: Michèle Smolkin's idea "Ban plastic and paper bags in stores" has been merged with this one.
"People bring their own bags and baskets"
NOTE: Heather Burton's idea "BAN plastic bags" has been merged with this one.
"Now is not the time to be dainty about this. If you are going to be buying enough stuff *ahem* items, to need a bag, you thought about it before you left the house. Meaning...you can bring your own bag. “But I always forget…” Well it will only take once or twice of having to schlep home dropping your toilet paper and lemons down Robson St. before it becomes a habit. It wont be hard I promise."
Even threatening a ban gets results. BC retailer associations were pressured into making a commitment to cut plastic bag use in half over a 5-year period. Let's go back to them when the 5 years are up, ask for proof they made the target, and then put a draconian tax on bags to finish the job!
I work in a grocery store and get to listen to all the excuses with a smile, and meanwhile watch piles and piles of disposable bags disappear all in one day. It's ridiculous!
Christopher Porter commented
San Francisco is doing it http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/08/03/MNUN1ENQJ0.DTL