Sorry for the confusing title. Basically before Unicode, a bunch of different standards for storing Chinese characters (also used in Korean and Japanese which also have some of their own derivatives) emerged. When Unicode sought to unify every standard they of course had to add compatibility for older standards so for all the different CJK standards they reserved this block. A bunch of fonts saw this space as free font estate and added a bunch of symbols in here for some reason.
Yeah… if you want to do nonstandard things like allocating a codepoint for a Wii icon, you should probably use the Unicode private use area instead.
It’s very weird… I wonder how they don’t get sued for including other companies’ logos. I only discovered this when trying to use FontForge to frankenstein fonts together and saw that Wii logo.