It’s a darned shame for the dogs, but let’s be real, it’s not like the airport service truck sees dogs on the airport grounds everyday. Sometimes you’re just surprised by what you see due to the context of the situation.
I’m sorry, but you are wrong about that. Our family has a service animal. As such, service animals are walked off the plane on leashes for potty breaks in the grass specifically designated for this use at airports.
Also, Delta Dash places crated dogs on the tarmac and their cutomers are warned to be sure to have their name and address attached to the dog, as well as the crate, due to the dogs sometimes escaping their crates and running lose on the tarmac. Airport personnel do know to watch for animals.