Mauser, I'll say buyer beware and be knowledgeable, no matter who you are buying from. Know how they do business, think about what you are buying, and if you don't like it, don't deal with them.
Lots of people seem to prefer buying from Wal-Mart. I'll tell them how I think it works, if they seem to want to hear it, but I think they then should choose for themselves what they are going to do.
Wal-Mart does drive down the costs of purchasing their goods and putting them in the stores, and does pass on some of the savings to consumers. That's their strategy for selling high volumes of goods, and that's their strategy for making profit. No one has to buy it. I don't think they should keep prices up to pass on profits to manufacturers when consumers are voting with their money in favour of lower costs and lower prices.
If any consumer doesn't know that higher quality tends to cost more and lower prices tend to buy lower quality, they are lazy. It isn't too complicated to figure out.