Both images appear perfectly symmetric to me, if symmetric means image=tranpose(image). However, I think this displays it better,
subplot(1,2,1)
imagesc(eye(2)*eps, [-1 1]*eps);
title('imagesc(eye(2)*eps, [-1 1])'), axis image
subplot(1,2,2)
imagesc(-eye(2)*eps, [-1 1]*eps);
title('imagesc(-eye(2)*eps, [-1 1])'), axis image


