The look he receives in return, from the giant spider still readying a killing blow on the petrified, weakly-bleating animal, is one of pure betrayal. The look he'd get from the goat would be gratitude, if the goat was sentient. It isn't.

She gestures with another leg to the other goats, all carefully snared in spiderthread so they can't get away from her. See, they'll have plenty of goats left! Better her than a goblin!