But a mom-and-pop supermarket in Chevy Chase, Md., claims it has the cleanest carts in town because it has installed one of the few high-tech, cart-cleaning systems in the metro D.C. area.
"There's always an assortment of bodily fluids from the kids that are always found [on the carts]" says Jay Kirsch, whose family has owned Chevy Chase Supermarket for three generations.
Other nasty things on carts include soiled napkins, as well as the saliva and germs when people sneeze, he adds. But that's not the case with the supermarket carts and baskets at his establishment.
"Hands down, they're the cleanest in town -- remember that we use the Pure Cart System that kills off 99 percent of all the harmful bacteria that could live on the cart," Kirsch says.
Think of the Pure Cart System as a mini car wash, inside the supermarket, for the carts and baskets.
"We run them through to make sure it's sanitized for the next person. It's a very simple process. It's remote-controlled buttons that we push. We turn it on, there's a mist that sprays," he adds.
The cleaning mist dries in 90 seconds and its safe, something shoppers like Anne Mayo and her 1-year-old daughter Josie appreciate.
"Especially because she rides in it. I wash my hands after I go to the grocery store, but she puts her thumb right in her mouth," Mayo says.
Kirsch says the cleaning system has become so popular that many customers are asking him to run their strollers through the Pure Cart machine and Chevy Chase Supermarket does it free of charge.