Shelters vs. Puppy Mills
Adopting a pet from the animal shelter not only benefits you, it helps an animal in need. Many dogs are awaiting an owner, and adopting from a shelter is a relatively inexpensive way to obtain a pet. Taking a dog home would also mean saving a life.
Be aware that puppy mills often mistreat and abuse animals in the process of making profit of of the sales of pure breds.
A video on puppy mills