As for passengers intruding into the galley, I would regard that as being just plain "pushy".
Actually I see it as being more accommodating than pressing the CC bell. If you need, say, a glass of water, pressing the bell means the CC has to make four journeys; galley to pax seat, back to galley, back to pax, back to galley. Whereas if the pax goes to the galley, the crew just has to pour the water.
Of course just waiting until CC come round would be the easiest on the CC but on some flights that could be several hours.