Do you mind when family and friends reach out and rub your belly? Some do it to me, and at first it was awkward, but I'm used to it now. Others stay away, I think they're waiting for me to ask if they want to touch. I'm waiting for baby to actually be DOING something when I'm with them so there's something to feel.
My mother warned me early on NOT to invite my grandmother to touch, because she thinks its private.