I don't get any reactions, no. I think food photography is fairly common now. You see it a lot. That's why I started to do it actually. I saw so many people doing it and I didn't care so why would others care? That was sort of how I was thinking.
The shop owner making a scene would be embarrassing. Shop owners tend to be a little more uptight about that sort of thing. I'm not sure why. They don't want people stealing their art ideas? Or comparing prices maybe - photo searches online? I generally don't take photos of shops though for that exact reason.
Yes, that's probably it. Since then, the experience created this habit of looking out for those signs and asking permission before snapping away.
These creative dishes are so beautiful, taking pictures would be the right thing to do before enjoying the flavors.