Sam wouldn't have put a walmart there if there weren't people, mostly on the lower income class, that were going to shop there.
I'm not saying that Walmart is not meeting demand by placing his stores where he places them. I'm saying that you and I and the majority of the population are not working for the people that shop at Walmart. Not that there's anything wrong with shopping at Walmart. Like I said before, those people who shop at Walmart are getting paid from someone else. Someone who probably does not shop at Walmart (a rich person). I feel like I'm really repeating myself here.