Yes,I certainly have done so!!! Now I tend to grate very few items as the feeling in my fingertips is not very good,so I can cut myself with no effort at all. When I was younger though, the damage was due to simple carelessness.
Yes, but I learned from it. I have cut myself pretty good a couple of times, once I even took a whole chunk of my fingernail off with the grater. Now I've learned better, and can know to slow down and how to hold what I'm grating properly.