A few months ago I made the switch to reusable grocery bags. I'm really glad I did. At first, I was struggling to remember to bring them in and actually give them to the cashier. Now it's just second nature to grab the bags out of the car and toss them on the belt at the registers.
It really has made life easier. You can fit so much more in those bags and they are much easier to carry. I can make a grocery trip that would normally take 10 plastic sacks fit into 3 or 4 of the reusable bags.
Plus, some of my local stores offer a 5 cent discount per reusable bag. (Target being one of them) CVS even has a program where you get a tag for your reusable bag. Then every 4th time you use it you get a coupon for $1 off your next trip. Nice! And they are ready made totes for daily life. They're really quite handy.
The environmental impact is an added bonus. Since I've been using my reusable bags I estimate that I have avoided bringing home at least 40 plastic sacks. Breaking that out over a year I figure I can avoid using around 250 plastic bags!
If you haven't started already, pick up one or two reusable totes and give it a try. You might like them as much as I do!