Though I love CoffeeScript, I feel it's very important to understand how JavaScript works. It's a great language, but only if you understand what is going on, and why you do have to use hasOwnProperty.
I'm working on it. I did mention that I'm learning Javascript at the same time. I should add Crockford's JavaScript: The Good Parts to my coffeescript resources list. Can you link me to an article explaining hasOwnProperty?