For a premium product, more expensive components and/or designs are used (. a switch + some extra circuit traces). The additional production cost of these may only be a few cents per unit, but they allow the products to be sold at a higher price because of the differentiation. Examples beyond the write-protect switches include things like speed class on SD or MicroSD cards – people will get very excited and snap up cheap cards on sale, but will never even consider whether they’re class 2, class 4, or class 8 (or higher) because most of the purchasers A) don’t even know that those options exist or what they mean and B) don’t care. On the other hand, people looking for speed (. professional photographers) are going to be purchasing class 10 cards and nothing but, and they’re going to pay a premium for them.