You left out the Both or Either choice in your poll.
Some people are right eye dominant and some are left eye dominant and it has nothing to do with 'handedness'.
I'm right handed, but most often shoot with my left eye to the viewfinder, because I am left eye dominant and it feels 'natural'.
However, my right eye is right up against the back of the camera when I do that. So when I shoot sports I use my right eye at the viewfinder, so I can watch the action with my left eye, aiding antisipation of the action. It takes a conscious effort to use my right eye and it took practice to learn to leave both eyes open, but when I did my images were better and sales went up.