Ive read there are mirror addresses for different speed gamepaks. Why?
It is cheaper (right now) to make low or slow speed gamepaks. As a result, Nintendo will probably use low speed gamepaks until prices drop even more. If you dedicate separate memory spaces for different speed gamepaks then this is an easy way for the hardware to automatically know what speed gamepack is being used and you could mix several different speed ROMs in the same gamepak if really needed.
