One of your statements was "They drain resources and get free care while offering no benefit other than satisfying maternal urges which were designed to work on human babies".
Any example of a dog offering a benefit other than satisfying maternal urges contradicts that statement.
In addition to the non-maternal urge satisfying benefits he named I'll give another: protecting human children. When I was around 4 our dog stopped me from going and picking up a rattlesnake. The dog blocked me from getting closer to the snake and barked until my Mom came to investigate.