Why are so many dogs being abandoned and end up in shelters?
A lot of people still buy dogs because they want to have “reputable, registered” breeders which can cost several thousand for a purebred. These “purebreds” come from puppy mills or boutique pet shops which only want to get profits and don’t care about the well-being of dogs. The dogs end up in the shelters because they were abandoned by owners, lost homes due to natural disasters, rescued from being eaten as a delicacy, aggressive towards previous owners.
Resources
https://www.humanesociety.org/resources/top-reasons-adopt-pet
https://www.pawfriendly.com/petcare/no-kill-animal-shelters.shtml#.XNC4zzZK2Ds