So that answers it. They exist soley to take money from people too stupid to figure out the price of things before buying. Then they have sales to sell to the other demographic that does. It's called price discrimination. Maybe they have more than one store in a location so one can have a sale that concious buyers buy from while the other keeps high prices and can still sell to their main margin generator. Having two stores still leaves a 50% chance that your sucker walks into the good store which is oddly more of a waste than having way more floor space than you need. So you expand it to five or so and have the sale at one store only, and only have a sale on anywhere half the time so the consious consumer class has to not only seek out which store has the best deal, of five, of stores that all bare the same name, but also be willing to wait for a deal when you find none after checking five stores. That will put 90% of the population into the non-consious class that you can get margins off of.