Skipping class is a waste of your tuition dollars. Going to class is an efficient use of your time. It will take you twice as long to find out what you missed, copy someone else's notes, etc., as it would to have gone to class yourself. When you skip, you miss class discussions - a chance to hear other students' questions and ask your own. Someone else's class notes will not make as much sense to you as your own.
Lectures often cover materials other than the text.
Professors tend to highlight what they consider most important - your clue as to what's likely to be on an exam. Much of your education comes from direct interaction with faculty, not just from reading a textbook. Your teachers are experts in their fields with experience to share. You may need a favor from a professor at some time - an incomplete, more time on an assignment, etc. You are responsible for all material covered in class, whether you were there or not.