It’s not as black and white as that all the time. Who’s the stranger? What power do they potentially have over you, how could they affect your life negatively or positively, now, or in the future? If you treat them how you wanna be treated, will they do the same to you? Does what you do around others, not caring what they think of you, mean the same thing to you that it does to everyone else around you at any point in time? Maybe one of those people doesn’t care like you, and decides that means it’s okay to start decapitating children wherever he or she is. Caring about, to a degree, what other people think about you is necessary to life. If you stink because you have an infection, but didn’t care that other people thought you stank, then you die of infection, etc. There’s levels to it. Strata. Shades of grey. If people around where you live thought you were a pederast, it would make grocery shopping, and everything, more difficult than if they didn’t, so it’d behoove you to think they might as well not, if you can help it.