Answer:
Yes, they are. Why they are more expensive is because they let you use the books they ship to you. Also, you don't have to travel around the world just to listen to a lecture abiut a subject, you can just stay at home, no money spent, and listen to the lecture at home. (This is my opinion) Most people say that online classes are more harder, but really it's not, you just need the right amount of money and you can join classes you want.
Hope this helps!