Because we didn't recruited peaseants at the end And we will not need it since we are winning the war
Just watch the cutscene of Rasthakan funeral and the Reunion of alliance leaderships, Wyrmbane and Nathanos said alliance is winning this war and they are near the victory, so horde is sucking in this war, not alliance. And horde was sending peasants to the war since the start, just watch how many orcs pawns that we kill in Stormsong as alliance.