People always make these irrelevent comparisons. The difference is, I don't have to buy from Wal-Mart. I can go to Target, K-Mart, Cosco, whatever, and I may end up finding what I'm looking for at a 20, 30, or even a 50% savings. You can't do that with gas/diesel because this industry operates in a cartel selling a product world economies MUST have in order to survive. Shopping around for gas prices is a waste of time since prices are strictly controled (within a few pennies) so they're basically the same for any given area. Also, I can more than likely do with the stuff from Wal-Mart much easier than I can do without gas...and the oil companies know this, which is why they get away with raping consumers...
So what do you want to see happen that will alleviate this "problem"?