I went to Walmart at 3AM and saw the Floor Stock Manager for the Automative section so I ask him what brand of oil sells the most. He says he can't keep stock of oil because it sells out so fast that he has to have it stocked every night. He did say that Mobil and Penzoil sells the most oil and interesting he says just the name Mobil and alot of them buy the Mobil Drive Clean. The third best seller was Castrol and then followed by Supertech. I ask him if they read the LABEL and he says no they don't. They look at price and what they see but more importantly the price is cheaper than other places. He says the average costumer sees dino is dino and they are all the same. So his final conclusion is why do so many people buy from Walmart is the price is cheaper from the outside, the selection and down the road with all their shopping.