We have reusable nylon bags and those are nice and sturdy. My local grocer... I line up my groceries on the belt in little piles and put one bag with each pile. I would think the point was obvious. They grab the bags and just throw whatever they want into each bag. raw meats mixed with boxed goods. heavy items on my eggs. I dislike going to my local grocer because there's no self-check option. I was a cashier for a while and got a lot of compliments and praise from my customers because I bagged smartly. It's not that hard to say "oh this is a freezer item, maybe I should put it with other freezer items".