A trip into Target is never a two minute visit. The ONLY time you leave an infant in the car is when you're filling the car with gas, and if you pay inside, then you take the infant inside.
Any other time you leave the car, the child comes with you.
Yes...even if it takes you 10 minutes to get the twins and toddler out of the car, spend 5 minutes in the store, and takes another 10 minutes to get the kids back in the car.
You NEVER leave kids in the car.