I think what you mean is. Everyone cares about what others think but some choose not to act on it. For instance if someone said you look like crap in school and you just kept walking on you would still care about their opinion on how you look like crap but you chose not to act on it and kept moving on with your life. Why? Because he is no one to impress.

Impressing people who have the power to make your life better is acting on what they think but if you don't see them as important then you won't act on it. It doesn't mean you don't care. It just means you don't care about impressing them.