Nvidia and AMD aren't really interested in making cards, they make only GPUs.
As for better brands: Sapphire, HIS, MSI, XFX, Gigabyte, Asus are among the good brands for AMD GPUs.]
There isn't one best: they are all good. Just check what you need, ones have better cooling, while another ones have longer warranty, etc.
I would have thought that if they made the cards then they could make extra cash? I know what you mean about better brands, but out of curiosity who would you say is the worse, just in your opinion