I believe money can be made in any field as long as you are good at it.
Engineering gives a safe charted out path to earnings in ways other courses don't, for eg, I don't know what a BSc graduate can do apart from going for MSc, or what kind of non-IT job options are available post BSc.
Coming to the advice, I believe it's easier to flow with the tide than against it. In India, it's common to have a B.Tech/B.Com degree, it gives you a wider base of people to be able to connect to, so why not have that advantage instead of trying to play it smartly by doing irregular courses.
Sure, if anybody has the guidance/knowledge to do those courses, it should be taken up as an addon, but seeing how India is not very equipped to deal with "special" cases in education, it pays off to do whatever everybody is doing.
Coming to your specific problem, I don't think 8-4 or 80% attendance is the problem. They're college students, they're bound to be flaky and non committed. You cannot force discipline on people who think they don't require it. They'll invest time when they feel the need for it. Until then, all you can do is wait.