When people ask "where are you from?" I think they are rarely trying to use that as a jumping point to know or understand you. Quite the converse, I think they are trying to find a shortcut to understanding you through their understanding of that place. They are looking to find a way to categorize you.They are trying to understand you through their knowledge or experience of people from that place (usually through stereotypes). For instance, I am an American born in Vietnam to American and Korean parents. I have lived in 13 countries and have spoken 7 languages. Consequently, they are never satisfied when I say I am an American because my look is more Asian. Americans are usually immediately satisfied when I say that my mother is Korean. They nod their heads like they understand and then they move on to a different topic having categorized me and having all the information they need to understand me. When I say I my mother is Korean to a Korean person, they look confused and ask again in another form. When I say I am American, they nod and move on. Whenever I give the long winded answer of where I was born, my ancestry, my current and/or last places of residence, I almost always get a dissatisfied look. The questioner is not able to satisfactorily categorize me and therefore remains unable to "relate" me to their limited idea of how a person from a certain area is supposed to act or be.
This speaker thinks that the question "where are you local?" is somehow different from "where are you from?" but it is the same thing only so unwieldy as to be unusable to ascertain the information the questioner is hoping for. Generally, when a person asks "where are you from?", that person merely wants a short cut so he/she doesn't have to go into the depth required to actually understand a person's background and how he/she might relate to it.