There are way, way too many brands of oil being marketed by the majors. How many different synthetic 5W-30 oils is just SOPUS marketing between the Shell, Pennzoil, Quaker State and Rotella labels plus all of the sub-brands under each label? It is crazy and inefficient, especially since for 99.9% of applications nobody will ever actually be able to tell a difference in engine performance or longevity. It gives us Oil OCD folks something to spend time on, but where is the actual value add????
That's just how it works these days. The point sometime isn't that the product doesn't sell, it's to prevent other products from taking up the same shelf space. So a lot of the majors actually pay for shelf space to have their products on there and pay enough to block out other companies. Walmart is a little tougher in that if it doesn't start to move, they'll kick them out after a while, but it can sit there for a little while. Mobil 1 was trying to push their annual protection oil at one point and it just didn't sell, they did take up a lot of shelf space for a while but those contracts must have expired and it doesn't take that much space anymore and the price came way down after it didn't sell.