When someone doesn't like you do care why they don't like you?
Don't care one bit
I just want to know if it's something I did and/or something I can fix.
Unless it's a girl.
Yes. I feel I have a right to know.
In the situation you cited, Don't care. There are many reasons, all of which have nothing to do with you. Maybe you remind then of a camp counselor when they were 10.
Not worth the energy.
The reason I asked this question I was volunteering today. This guy walked up who I was helping and just told me he didn't like me and I don't mind it but I wonder why he doesn't like me?
That entirely depends on the person.
Depends on the person. If it was a close friend then yes. Someone I never got along with then no.