A can of brand product and cheapo product cost roughly the same to produce. Both are sold at a profit.
If the producer produced only name brand products at the higher price point, some price-sensitive shoppers would buy goods made by a different producer. This would reduce the producer's profits.
If the producer produced only cheapo products at the lower price point, price-insensitive shoppers will end up paying less money than if a brand name product were available on the same shelf. This will also reduce the producer's profits.
The profit maximizing strategy is to sell basically the same product at different price points, trying to nudge higher income (less price sensitive) buyers to pay more than necessary via nicer packaging, better shelf placement, and advertising.
This is why many inexpensive store brand products are identical to more expensive brand name products, yet the store brand equivalent has not driven the brand name out of the marketplace. Companies are better approximations of knowledgeable, rational economic agents than consumers are.