So if soneone followed you into your garage, as happened to the OP, you'd find that nothing to be scared about? You are infinitely braver than I am!
That was definitely scary for the op. I am referring to beggars either stopping you on the street or coming to your door and how common that is in cities. In the vast majority of situations like this, nothing to be afraid of. I would not open my door and I don't generally give to people on the street.