Not that this is true in every situation, but a good majority of the time whenever people react negatively to something you deem as being positive for you, it's because of jealousy. A reaction of "shock" is a mostly negative one by definition. In this case I would bet that the "shocked" reaction from some of these people is more of a "Who are you to leave us" or "oh, you're too good to live here with us" reaction, but they can't actually say that without looking silly and selfish. Just my two cents.