The mechanical behavior upsets Grendel. Is he demonstrating more free will, more meaningful behavior than the goat?

Grendel is desperately trying to find meaning in this meaningless goat climbing and climbing. Does the goat have no free will, does Grendel have no free will? Grendel discovers a mountain goat climbing up toward his mere. He warns the goat off, but recognizes that goats are meant to climb, so it will keep climbing. He throws a boulder at it, but misses. Becoming more and more frustrated, Grendel warns the goat again then tosses a broken tree-trunk at the goat. A limb catches the goat and nearly knocks it off the mountain, but still the goat attempts to climb. Grendel hits it with a stone, cracking its skull, but still the goat climbs. Grendel draws back from the goat and throws a rock at it, smashing its face. The monster smiles at his own sense of being threatened by a stupid animal. I think Grendel is merely manipulating his environment to give himself the illusion of free will.