Without such a skill it will be hard for you to keep up with the rapid pace of technology. Despite the high cost of books, full blown college courses are much more expensive. The price tag on a college degree is even higher still. I see several points. In a course, the instructor filters and organizes the material into chunks that are easier to digest.
Books tend to be long and comprehensive in an effort to be all things to all people.
Critical material gets obscured by less important information. In a course the critical information is highlighted by the instructor. In a course you get the opportunity to interact with your instructor and with your fellow students. This interaction allows you to get questions answered, pursue additional topics of interest to you, and learn about how various aspects of a subject fit together in the big picture. In a course you get access to college resources.