^ Yes the thing is instead of taking your advice they will blame you for "thinking that you can tell you parents" Like i said You teach those who are willing to learn. Its futile.
Pendu........it can also depend on how one approaches their parents. For example......if I approach my parents in a defensive manner....where I'm all huffed up....and I'm yelling at them.....and telling them ALL the things they've done wrong.............they're more likely to get defensive.
However.....if I speak to them very calmly and focus on the positive......and also try to acknowledge their point of view....while calmly presenting my side of the argument...........it might AT LEAST encourage them to think about my point of view.