When it comes to where a person goes to find a pet, people have a lot of opinions, especially in regards to purchasing a pet vs adopting.
While some people may push the "adopt, don't shop" mentality a little too strongly for my taste — all animals deserve loving homes, regardless of the motives of the breeder — getting more people to adopt rescued dogs and cats is a net positive. Fewer potential customers for backyard breeders or puppy mills will disincentivize the practice.