People use bikes for shopping. Many don't have racks or bag systems to carry their belongings. Therefore I see people riding with grocery bags hanging off of their bikes. This obviously affects control of the bike. However, it gets worse if the bags are not the same weight. There will be a turning force created if one bag is heavy and the other light. So pack bags equally if you bike with goods handing off the side.

Try to get a bag system to attach the weight to your bicycle frame....it will make shopping safer.