I think most people actually think in terms of "little, medium, a LOT" of pain. And usually my pain med orders also reflect that (x for moderate pain, y for severe pain). I also think that patients worry about being properly medicated NOW to provide good pain relief for the pain that is on its way back but hasn't really arrived yet.
I'm really aggressive with treating pain but I hate the pain scale. It's so subjective I don't find it terribly useful. One patient with 7/10 pain just wants Tylenol, another wants the morphine. Just tell me how bad it is and if you need the big guns or something lighter.