system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are we supposed to "adopt, don't shop"? Why does it matter as long as the pet finds a loving home, right?
gpt
The idea is that buying animals in a pet shop encourages bad breeding practices.  People churn out animals for profit with no thought for the welfare of the animals being bred. 

If you adopt you are taking in an animal that needs a home, but you are not financially rewarding someone for potentially unscrupulous behavior. 

There are reputable breeders out there of course, but if you are walking into a pet store it's hard to tell if the animal came from one of these.