None of the slices are the same. Some are wide, others narrow. Each one faces in a slightly different direction. These differences are a result of the Moon's motion around its tilted, elliptical orbit. Each full Moon occurs at a different point in that orbit, and so we see it from a slightly different distance and angle.
Scroll up and down past the slices; they seem to rock back and forth. The rocking motions are called libration; because of them we can see 59% of the Moon's surface rather than the 50% you might have learned in school. So pay attention to the next full Moon (Jan 28th). It's as unique as you are.