What i've never understood about coffeescript is, since it compiles to javascript, why not just learn to write javascript in the idioms that coffeescript generates?

No one would have a problem suggesting that a developer who only used jQuery actually learn how to code in standard js without the syntactic sugar. CS doesn't compile to bytecode, it compiles to an actual, human-readable and editable language.

So why not just learn that style of javascript and save yourself the hassle of pretending there's a second scripting language for the web?