The pricing of Store brands and Brand names

Although it is not the first time that I saw it, but this may be the first time I am writing about it. I went to a grocery store to buy the usual stuff of water, milk and other things which caught my eye while browsing through stuff which are on sale and I noticed something which made me a bit curious. A brand item was on sale for exactly the amount of the store brand and it was not one item but several items stacked side by side. Although it does not happen quite often, but when a brand item is on sale for exactly the store brand item, why would anybody buy a store brand? And trust me I have used both the store brands and the brand names and there is still a difference of quality. I don’t understand that if a brand name is selling for exactly the same dollar amount as a store brand, why not the store brand would lower its price to compete with them.

I am curious guy and this intrigues me a lot. I would not buy a store brand if the price of a Brand name is the same as the store brand no matter how loyal I am feeling or how much I have gotten attached to the store brand. I buy store brand since they are a much cheaper than the brand name but if there is a sale which equates or even lowers the brand name prices to what I usually pay for the store brand, I will definitely opt for the brand name every time.