I'm confused at why people wear backpacks into supermarkets.
Do you people also wear your backpacks into movie theaters?
I guess you don't walk or ride a bike much then, because it's perfectly normal to carry a backpack around with you in those situations. I have three supermarkets, a drug store, and two department stores within a couple minutes walking distance of my house. Why take the car when you can enjoy a good walk and carry your groceries or other items home in your backpack?
And yes, I see plenty of people with backpacks in movie theaters. That's usually how they smuggle candy and sodas past The Fuzz.