Many times, company A is - say, a company that is not very worker friendly. They are in a hostile region. They have VERY low manufacturing costs yet still a reasonible quality assurance.
Not many company's in the US would buy from these types of establishments, then just resell their product. They would 'brand' the products and basically, be the marketing division of the manufacturing company.
That is at the very least.
I've heard that CKYS adds their own code to the devices to establish more of what they are trying to do. Also, their logo is cooler. :)