One thing to consider, too, from a former grocery store clerk:
We were trained to keep cleaning supplies in a separate bag from food. Ever have a box of raisins and a box of dryer sheets spend any amount of time in a bag together? You bought milk and shampoo. More than likely, he's get shit for NOT doing it than he would for doing it too much.
I actually got sworn-at by a customer who was upset that U put his dozen eggs on the top of the items in the bag. "Now, what the fuck happens when the fucking eggs break? Egg gets all-the-fuck over everything under it in the bag, doesn't it?! Think for a minute!"
I went to target today, and they put my dryer sheets and soap in a small bag, tied it shut, and put it in one of my two other larger bags which did contain food items. My girlfriend would have been pissed that they "wasted" the extra bag, but I appreciated it as I'm not a fan of BBQ Soap Potato Chips.