no it isn't required that a robot be able to pick the "rocks" and "cells" up off the ground. given the fragility of the orbit balls in this competiton, picking the balls up without breaking them will be and interesting challenge for the teams that decide to take that road.
and to reduce bias, the human loaded aspect in this game is also rather risky. while it is much simpler to design an open hopper on the robot, the simple fact that you r own alliance would be throwing balls at you robot to reload it leads to the possibility of them accidentally leand them in the trailer as well.
but the reverse is also true, the other alliance could accidentally reload your bot instead of hitting the trailer.
