Hmm. I agree about the wig color thing, but sometimes it's hard to find the right colored wig. A lot of things could factor into the decision making process.
For example, the character's hair may vary by which art the cosplayer is going off of, and if the character has black hair, the color of highlights may need to be taken into account. A lot of characters with black hair will have an odd color of highlights. (blue, green, purple, etc.) It's also not the easiest thing to tell what a wig will look like in real life by the color shown on the website, for those who order wigs online. (Most people I know do) An off color might also be the product of trying to dye it and having it come out the wrong color. D:
Just the same, though, it is kind of irksome to see a wig that is completely the wrong color. ) =