The Epitome of Lazy

We ttok the dogs for a walk the other night through the park around the lake across the street from our new house. Along the park are large houses and when it's dark out, you can see inside as you're walking along because there are no large fences (they're not allowed). As we're walking by, we see a dog inside one of the houses and it looks like he's running. Confused, we take another look and see that he's running on a treadmill. Are his owners so lazy that they can't even take him for a walk along the pathway behind their own house?
Unbelieveable...