Burnt Steak, the other side of the coin is lazy supermarket employees who resent having to actually do their jobs– I used to be a supermarket cashier and I had a family come through with a big order. They were paying in food stamps and the total went over their remaining balance, so they had to decide what to keep and what to put back. The parents were also trying to calm down their hysterical young children and they had a taxi waiting outside. They were clearly very overwhelmed and struggling and my heart was breaking for them. My manager, on the other hand, just scowled and loudly complained about the number of items that we would have to return to the shelves, including some produce and frozen items.
But yes, those who are in less desperate situations should return their own items. They should also return their carts to the designated cart return in the parking lot, not just leave them in a random spot in the parking lot (ch”v the cart could start rolling and hit another car, not to mention the extra and unnecessary work for workers who are underpaid and under-appreciated). It takes 5 extra seconds; just do the right thing.