Grocery shopping with dad is less shopping than it is a brisk scavenger hunt.
Mom gave him a list of food, and he will wander around, somewhat lost, until he finds each item. If at all possible, try to limit the amount of time he spends at the meat counter. If you’re lucky, dad will be in and out of a grocery store in 15 to 20 minutes, but he can easily spend just as long looking at meat and trying to make conversation with the butcher.