Actually i find the 'next' page button too low.
I hold it with my fingers at its centre of mass, which is the middle of the back of the kindle. This places my thumb right above the 'back' button instead of 'next'.
Also since the thumb acts as the other part of my 'pincer' grip on the kindle, the fact that the buttons are on the edge of the bezel means that i won't be accidentally pressing them whilst holding my kindle tight. Yet it isn't too far away for my thumb to slide off the bezel and depress the buttons.
So yes, each to their own