When grocery shopping, you should always give your shopping cart handle and seat/basket area. Those areas tend to get the dirtiest with bacteria from things like leaking packages of meat or poultry, unwashed produce or items that have previously fallen on the floor, and even leaking baby diapers from kids sitting in the seat area.
And of course, Covid has brought a whole new reason to ensure your shopping cart is clean when you use.
While some grocery stores supply sanitizing wipes, they are often either all gone or dried out. Some grocery stores are sanitizing their carts between shoppers, but it is always best to clean it yourself. Always keep a ziploc with sanitizing wipes with your coupons or your reusable shopping bags. This way you will always have some with you to clean your cart.
With wipes, wipe the entire handle area. Wipe the seat area, including both sides of the plastic seat that flips.