I do if I'm taking a break and they pass by. I love dogs.
In relation to this, there's a dog park that I pass by on the regular path I ride on. One dog that's there just about everyday seems to love bikers. He can spot me or any rider meters away then starts sprinting in the same direction by the fence. It's become a fun ritual now where I sprint with him until the fence ends. Then he turns around and waits for his next "victim". lol