Sometimes people ask me, "Why do you care?" About some thing that they ostensibly don't care about.
Caring is important. Not caring is harmful.
I don't consider people less valuable if they are strangers. So many people will one day influence my life, who are now strangers to me. They all have value. Others, who will not be in my life, also have value. Their opinions do, as well.
I am ultimately connected to everyone. Therefore, I find it valuable to correct incorrectness when I can.
You could say I'm opposed to the church of "Honey Badger Doesn't Give a Fuck". Honey badger ought to give a fuck. People not giving a fuck - about the world, about people - is a disease. It's what is causing most of our trouble.
To not care about others is, ultimately, to not care about ourselves. Eventually, the not caring comes around, and bites us all in our collective ass.