Everyone has brought up good points about stability. Initially, I thought it sounded kind of like a good idea because too many people get animals they can't take care of, so this option would be better for them (especially since they mention the people are evaluated and her clientele consists of people in the service, elderly people and people in apartments). However, I agree that volunteering at the shelter or being a foster parent to get experience with animals is a much better choice.
I have to wonder what affect this will have on the animals? If they are happy and ok with the situation, then that's good...but I would imagine it would take very flexible dogs to be ok with it.