Hmm, I wonder, if they want to make money out of it as well or not. My question is why I would spend 150$ on a online course, that I can get on edX or elsewhere for free?
You can take the course for free, but you won't get credit for it. From the Udacity blog:
"Living up to our promise to always provide a free path to high-quality education, we are also offering these courses free of charge as conventional MOOCs, but this path will not include instructor access, additional support services, or a path to college credit."
what is the catch :?