There are not a lot of yorkies in shelters here either. I'm in IL and when they do come from a mill it is usually IN of OH from a rescue that cannot handle what they are already overwhelmed with. There recently was an article about a mill in S. IL that was really bad but that is more of an exception than the rule in this area.
I think you are correct in saying it is the need for the type of rescue that you do which is specific to your area. If there are a lot of mills in your state that is what you will see in your rescue, it there are more owner surrenders that is what you will deal with. I have seen more turn overs from petshop purchases were the dogs are severely ill and need big money surgery. It's demographics.
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