Why are people whose hair is generally some shade of orange or auburn called redheads? Their hair is orange, not red!
And "ginger" which some people use a derogatory term, is actually kind of a tan color on the outside of the root, and more yellow than orange in its ground form, so why use the term ginger either? And ginger ale is downright yellow!
Anything from hair the color of a new penny to an almost-but-not-quite-brown the shade of rusting iron is called a redhead. Why?
Any why do people who learn I like winter, and snow, automatically assume I am a skier?
Do you have questions you wonder about?
For the record, although I do ponder these things, the definition of imponderables is "a factor that is difficult or impossible to estimate or assess."