Dogs, you got the story wrong. The reason a WallMart executive suggested having cashiers gather up carts in the parking lot was to force older ones who had worked for Wall Mart for years to leave because --gasp-- when you get to be fifty you don't have the strength you did when you were twenty.
The idea, clearly stated in the leaked memo was that this would enable WallMart to get rid of their longtime employees without risking age discrimination suits. So if you only had young people working then health costs would be lower. (in all supermarket and stores with carts, cashiers are not the ones to bring them in so it coulnd't be argued that this was in cashiers' job description).
Of course those older cashiers would have tried, because they wouldn't want to lose their jobs, and as a result would come down with severe disabilities that the rest of us would have had to pay for. Surely you must be aware that Wall Mart employees get paid so little that many of them are elligible for food stamps and those who are parents for Medicaid? The new Wall Mart health insurance is extemely skimpy. So again we, the tax payers, have to cover the costs that WallMart saves.
And by the way, check it out, WallMart is far from being the least expensive store around...