.......is this abuse?

my neighbor who lives across the street owns a golden retriever which to my knowledge are quite active dogs. i've never once since the day they brought her home three years ago seen them take her for a walk. i am always sitting out on my french doorstep so i can see what is going on pretty easily as they live directly across the street from me. the family is overweight and uses their car as an only means of transportation. they have a small backyard where the dog eliminates but thats about the only outdoors it ever sees. i own a shih tzu, a very small dog, who gets more energy than this golden retriever. its escaped out of its backyard numerous times and runs back and forth across the street. one time i had to grab her by her collar and drag her back home, where the owner was sleeping and had no idea how she escaped the backyard. my heart breaks for this dog as i feel it is never walked. its home inside all day. is this abuse or should i mind my own business?