If you overly rely on the computer assistance during the learning stage, there are fundamental principles you won't get a firm grasp on, and then you'll be at a disadvantage if you need it later. As someone who did use calculus after school, I'm glad I actually learned the subject.

You're right that most people don't need to know calculus in their lives, but to my knowledge calculus also isn't generally required to get through college/university for most people, so it's fair to assume that the people in the course are there because they need or want to learn it. When I was a TA for calculus, most of my students were pre-med, engineers, or in other sciences.